[llvm] [AMDGPU][NFC] Enable gfx942 for more tests (PR #154363)

[Janek van Oirschot via llvm-commits]

JanekvO wrote:

I've rebased locally on top of changes in #154115 and it does affect about 28 of the 37 tests I'm enabling gfx942 for here; let me know if I should cut the amount of tests adding in this PR to only those 28.

https://github.com/llvm/llvm-project/pull/154363