[llvm] [AMDGPU] Rewrite GFX12 SGPR hazard handling to dedicated pass (PR #118750)

[Jay Foad via llvm-commits]

https://github.com/jayfoad approved this pull request.

Looks like all comments have been adressed. The lit test changes look reasonable too, from a quick skim.

https://github.com/llvm/llvm-project/pull/118750