[clang] [llvm] [AMDGPU][GFX12] Add new v_permlane16 variants (PR #75475)

[Piotr Sobczak via cfe-commits]

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

LGTM

You could also update existing permlane tests with run lines for gfx12:
* test/CodeGen/AMDGPU/llvm.amdgcn.permlane.ll
* test/CodeGen/AMDGPU/vcmpx-permlane-hazard.mir

This can also be a separate patch.

https://github.com/llvm/llvm-project/pull/75475