[llvm] [AMDGPU][GFX12] Add tests for {image/flat}_atomic_pk (PR #78683)

[Jay Foad via llvm-commits]

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

LGTM, thanks. Don't forget to remove "image" from the description when you squash-and-merge.

https://github.com/llvm/llvm-project/pull/78683