[llvm] [AMDGPU] Get rid of the +wavefrontsizeXX,-wavefrontsizeXX in MC tests (PR #99001)

[Stanislav Mekhanoshin via llvm-commits]

rampitec wrote:

Change is massive. But this is test only. And only simplification.

https://github.com/llvm/llvm-project/pull/99001