bazel: create genrules to produce debs and RPMs without arch-specific names

[ixdy]

What type of PR is this?
/kind bug
/kind cleanup

What this PR does / why we need it: this is a follow-up to #73930.

In that PR I implemented support for cross-compilation using Bazel.

One issue I ran into is that the pkg_deb and pkg_rpm rules have an architecture attribute which is used in their package metadata, but is also used in the output filenames. (For example, pkg_deb actually creates both a $NAME.deb and a $NAME-$ARCH.deb.) Bazel disallows output filenames to be configured - you can't do something like

  out = select(...),

and similarly disallows configuring attributes which affect output filenames (like architecture).

To work around this, instead of configuring the architecture attribute, I used macros and list comprehensions to create multiple rules, each with a -$ARCHITECTURE suffix in their name.
This meant that the debs and RPMs now had different filenames.

I created aliases to maintain the old target names, but these aliases had no effect on the output filenames. Thus downstream projects like Kind were broken, as the debs had new filenames.

In this PR I'm basically restoring the old end-user functionality by replacing the aliases with simple genrules that copy to the non-arched filename. The arch-specific outputs still exist, but are generally to be used indirectly.

Which issue(s) this PR fixes:
Fixes kubernetes-sigs/kind#336

Does this PR introduce a user-facing change?:

NONE

/assign @BenTheElder
cc @neolit123

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: ixdy

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[spiffxp]

/priority important-soon
/sig release
/milestone v1.14

[spiffxp]

/lgtm