fix: Set MSRV for internal packages

### What does this PR try to resolve?

Correctly communicates the MSRV we support to our users.

For packages that are more generally mean to be used by other people, I've punted on for now (see ehuss' comment on this PR).  We'll likely need to figure this out for #12432 though

### Additional information

This is prep for a future change which will have us use a fixed rust version for the semver tests with a PR updating them.

Update cargo

13 commits in 2cc50bc0b63ad20da193e002ba11d391af0104b7..925280f028db3a322935e040719a0754703947cf
2023-08-22 22:43:08 +0000 to 2023-08-25 21:16:44 +0000
- string leek is stable (rust-lang/cargo#12559)
- refactor: Pull out cargo-add MSRV code for reuse (rust-lang/cargo#12553)
- Contrib: Add process for security responses. (rust-lang/cargo#12487)
- Support dependencies from registries for artifact dependencies, take 2 (rust-lang/cargo#12421)
- fix(toml): Improve parse errors (rust-lang/cargo#12556)
- Create dedicated unstable flag for asymmetric-token (rust-lang/cargo#12551)
- chore(deps): update latest msrv to v1.72.0 (rust-lang/cargo#12549)
- changelog: add link to CVE-2023-40030 (rust-lang/cargo#12550)
- refactor(install): Move value parsing to clap (rust-lang/cargo#12547)
- fix: Set MSRV for internal packages (rust-lang/cargo#12381)
- doc: fix two links to tracing docs (rust-lang/cargo#12537)
- use AND search when having multiple terms (rust-lang/cargo#12548)
- fix(log): Use a more compact relative-time format (rust-lang/cargo#12542)

r? ghost

Set and verify all MSRVs in CI

### What does this PR try to resolve?

Allow us to advertise an MSRV for all public packages, unblocking #12432.

Packages are broken down into two MSRV policies
- Internal packages: `rust-version=stable`
- Public packages: `rust-version=stable-2`

To support this
- RenovateBot will automatically update all MSRVs
- CI will verify all packages build according to their MSRV

Since this takes the "single workspace" approach, the downside is that common dependencies are subject to each package's MSRV.  We also can't rely on `-Zmsrv-policy` to help us generate a lockfile because it breaks down when trying to support multiple MSRVs in a workspace

### How should we test and review this PR?

Per commit

### Additional information

#12381 skipped setting some MSRVs because we weren't sure how to handle it.  For `cargo-credential`, we needed to do something and did one-off verification (#12623).  `cargo-hack` recently gained the ability to automatically select MSRVs for each package allowing us to scale this up to the entire workspace.

I don't know if we consciously chose an MSRV policy for `cargo-credential` but it looked like N-2 so that is what I stuck with and propagated out.
- Without an aggressive sliding MSRV, we discourage people from using newer features because they will feel like they need permission which means it needs to be justified
- Without an aggressive sliding MSRV, if the MSRV at one point in time works for someone, they tend to assume it will always work, leading to frustration at unmet expectations.

I switched the MSRV check to `cargo check` from `cargo test` because I didn't want to deal with the out-of-diskspace issues and `check` will catch 99% of MSRV issues.

Potential future improvements to `cargo-hack`
- Allow `--version-range ..stable` so we can verify all MSRVs that aren't stable which would bypass the diskspace issues and allow us to more easily use `cargo test` again
- Verify on a `cargo package` version of a crate (taiki-e/cargo-hack#216)

Pkgsrc changes:

 * Remove NetBSD-8 support (embedded LLVm requires newer C++
   than what is in -8; it's conceivable that this could still
   build with an external LLVM)
 * undo powerpc 9.0 file naming tweak, since we no longer support -8.
 * Remove patch to LLVM for powerpc now included by upstream.
 * Minor adjustments, checksum changes etc.


Upstream changes:

Version 1.74.1 (2023-12-07)
===========================

- [Resolved spurious STATUS_ACCESS_VIOLATIONs in LLVM]
  (rust-lang/rust#118464)
- [Clarify guarantees for std::mem::discriminant]
  (rust-lang/rust#118006)
- [Fix some subtyping-related regressions]
  (rust-lang/rust#116415)

Version 1.74.0 (2023-11-16)
==========================

Language
--------

- [Codify that `std::mem::Discriminant<T>` does not depend on any
  lifetimes in T]
  (rust-lang/rust#104299)
- [Replace `private_in_public` lint with `private_interfaces` and
  `private_bounds` per RFC 2145]
  (rust-lang/rust#113126)
  Read more in
  [RFC 2145](https://rust-lang.github.io/rfcs/2145-type-privacy.html).
- [Allow explicit `#[repr(Rust)]`]
  (rust-lang/rust#114201)
- [closure field capturing: don't depend on alignment of packed fields]
  (rust-lang/rust#115315)
- [Enable MIR-based drop-tracking for `async` blocks]
  (rust-lang/rust#107421)

Compiler
--------

- [stabilize combining +bundle and +whole-archive link modifiers]
  (rust-lang/rust#113301)
- [Stabilize `PATH` option for `--print KIND=PATH`]
  (rust-lang/rust#114183)
- [Enable ASAN/LSAN/TSAN for `*-apple-ios-macabi`]
  (rust-lang/rust#115644)
- [Promote loongarch64-unknown-none* to Tier 2]
  (rust-lang/rust#115368)
- [Add `i686-pc-windows-gnullvm` as a tier 3 target]
  (rust-lang/rust#115687)

Libraries
---------

- [Implement `From<OwnedFd/Handle>` for ChildStdin/out/err]
  (rust-lang/rust#98704)
- [Implement `From<{&,&mut} [T; N]>` for `Vec<T>` where `T: Clone`]
  (rust-lang/rust#111278)
- [impl Step for IP addresses]
  (rust-lang/rust#113748)
- [Implement `From<[T; N]>` for `Rc<[T]>` and `Arc<[T]>`]
  (rust-lang/rust#114041)
- [`impl TryFrom<char> for u16`]
  (rust-lang/rust#114065)
- [Stabilize `io_error_other` feature]
  (rust-lang/rust#115453)
- [Stabilize the `Saturating` type]
  (rust-lang/rust#115477)
- [Stabilize const_transmute_copy]
  (rust-lang/rust#115520)

Stabilized APIs
---------------

- [`core::num::Saturating`]
  (https://doc.rust-lang.org/stable/std/num/struct.Saturating.html)
- [`impl From<io::Stdout> for std::process::Stdio`]
  (https://doc.rust-lang.org/stable/std/process/struct.Stdio.html#impl-From%3CStdout%3E-for-Stdio)
- [`impl From<io::Stderr> for std::process::Stdio`]
  (https://doc.rust-lang.org/stable/std/process/struct.Stdio.html#impl-From%3CStderr%3E-for-Stdio)
- [`impl From<OwnedHandle> for std::process::Child{Stdin, Stdout, Stderr}`]
  (https://doc.rust-lang.org/stable/std/process/struct.Stdio.html#impl-From%3CStderr%3E-for-Stdio)
- [`impl From<OwnedFd> for std::process::Child{Stdin, Stdout, Stderr}`]
  (https://doc.rust-lang.org/stable/std/process/struct.Stdio.html#impl-From%3CStderr%3E-for-Stdio)
- [`std::ffi::OsString::from_encoded_bytes_unchecked`]
  (https://doc.rust-lang.org/stable/std/ffi/struct.OsString.html#method.from_encoded_bytes_unchecked)
- [`std::ffi::OsString::into_encoded_bytes`]
  (https://doc.rust-lang.org/stable/std/ffi/struct.OsString.html#method.into_encoded_bytes)
- [`std::ffi::OsStr::from_encoded_bytes_unchecked`]
  (https://doc.rust-lang.org/stable/std/ffi/struct.OsStr.html#method.from_encoded_bytes_unchecked)
- [`std::ffi::OsStr::as_encoded_bytes`]
  (https://doc.rust-lang.org/stable/std/ffi/struct.OsStr.html#method.as_encoded_bytes)
- [`std::io::Error::other`]
  (https://doc.rust-lang.org/stable/std/io/struct.Error.html#method.other)
- [`impl TryFrom<char> for u16`]
  (https://doc.rust-lang.org/stable/std/primitive.u16.html#impl-TryFrom%3Cchar%3E-for-u16)
- [`impl<T: Clone, const N: usize> From<&[T; N]> for Vec<T>`]
  (https://doc.rust-lang.org/stable/std/vec/struct.Vec.html#impl-From%3C%26%5BT;+N%5D%3E-for-Vec%3CT,+Global%3E)
- [`impl<T: Clone, const N: usize> From<&mut [T; N]> for Vec<T>`]
  (https://doc.rust-lang.org/stable/std/vec/struct.Vec.html#impl-From%3C%26mut+%5BT;+N%5D%3E-for-Vec%3CT,+Global%3E)
- [`impl<T, const N: usize> From<[T; N]> for Arc<[T]>`]
  (https://doc.rust-lang.org/stable/std/sync/struct.Arc.html#impl-From%3C%5BT;+N%5D%3E-for-Arc%3C%5BT%5D,+Global%3E)
- [`impl<T, const N: usize> From<[T; N]> for Rc<[T]>`]
  (https://doc.rust-lang.org/stable/std/rc/struct.Rc.html#impl-From%3C%5BT;+N%5D%3E-for-Rc%3C%5BT%5D,+Global%3E)

These APIs are now stable in const contexts:

- [`core::mem::transmute_copy`]
  (https://doc.rust-lang.org/beta/std/mem/fn.transmute_copy.html)
- [`str::is_ascii`]
  (https://doc.rust-lang.org/beta/std/primitive.str.html#method.is_ascii)
- [`[u8]::is_ascii`]
  (https://doc.rust-lang.org/beta/std/primitive.slice.html#method.is_ascii)

Cargo
-----

- [fix: Set MSRV for internal packages]
  (rust-lang/cargo#12381)
- [config: merge lists in precedence order]
  (rust-lang/cargo#12515)
- [fix(update): Clarify meaning of --aggressive as --recursive]
  (rust-lang/cargo#12544)
- [fix(update): Make `-p` more convenient by being positional]
  (rust-lang/cargo#12545)
- [feat(help): Add styling to help output ]
  (rust-lang/cargo#12578)
- [feat(pkgid): Allow incomplete versions when unambigious]
  (rust-lang/cargo#12614)
- [feat: stabilize credential-process and registry-auth]
  (rust-lang/cargo#12649)
- [feat(cli): Add '-n' to dry-run]
  (rust-lang/cargo#12660)
- [Add support for `target.'cfg(..)'.linker`]
  (rust-lang/cargo#12535)
- [Stabilize `--keep-going`]
  (rust-lang/cargo#12568)
- [feat: Stabilize lints]
  (rust-lang/cargo#12648)

Rustdoc
-------

- [Add warning block support in rustdoc]
  (rust-lang/rust#106561)
- [Accept additional user-defined syntax classes in fenced code blocks]
  (rust-lang/rust#110800)
- [rustdoc-search: add support for type parameters]
  (rust-lang/rust#112725)
- [rustdoc: show inner enum and struct in type definition for concrete type]
  (rust-lang/rust#114855)

Compatibility Notes
-------------------

- [Raise minimum supported Apple OS versions]
  (rust-lang/rust#104385)
- [make Cell::swap panic if the Cells partially overlap]
  (rust-lang/rust#114795)
- [Reject invalid crate names in `--extern`]
  (rust-lang/rust#116001)
- [Don't resolve generic impls that may be shadowed by dyn built-in impls]
  (rust-lang/rust#114941)

Internal Changes
----------------

These changes do not affect any public interfaces of Rust, but they represent
significant improvements to the performance or internals of rustc and related
tools.

None this cycle.