Fix broken hyperlink

[jyn514]

r? @nico-abram

[nico-abram]

This fixes the broken link, but it still seems slightly confusing to me

The paragraph says:

As documented above, this will build a functional stage1 compiler as part of running all stage0 commands (which include building a std compatible with the stage1 compiler) as well as the first few steps of the "stage 1 actions" up to "stage1 (sysroot stage1) builds std".

But there is no mention of stage1 or 0 in the linked-to section, and also no mention of "-i"

[jyn514]

Hmm, maybe it would be better to link to https://rustc-dev-guide.rust-lang.org/building/bootstrapping.html#stages-of-bootstrapping instead?

[nico-abram]

Maybe. I'm not sure skipping ahead to the next chapter would be better, and this is certainly better than the broken link. Anyone curious will probably keep on reading and reach the next chapter

[jyn514]

Actually https://rustc-dev-guide.rust-lang.org/building/how-to-build-and-run.html#building-the-compiler is probably a better place, let me try that.

[nico-abram]

That seems perfect to me, it's behind and more or less explains both -i and --stage

[jyn514]

Awesome, thanks for the review!

r? @spastorino to double check I didn't miss a typo