Auto merge of #51725 - Mark-Simulacrum:no-llvm, r=kennytm
Do not build LLVM tools for any of the tools
None of the tools in the list should need LLVM tools themselves as far as I can
tell; if this is incorrect, we can re-enable the tool building later.
The primary reason for doing this is that rust-central-station uses the
BuildManifest tool and building LLVM there is not cached: it takes ~1.5
hours on the 2 core machine. This commit should make nightlies and
stable releases much faster.
Followup to https://github.com/rust-lang/rust/pull/51459, r? @kennytm
I'm mostly relying on CI to test this so probably don't roll it up; I'm not sure how to (and not particularly inclined to) wait for multiple hours to test this locally. I imagine that the failures should be fairly obvious when/if encountered.