[llvm] [AMDGPU][RFC] Combine asm and disasm tests. (PR #92895)

[Scott Egerton via llvm-commits]

ScottEgerton wrote:

I didn’t realise sed had been ported to Windows. Is there a plan to expand this to more tests? It looks good to me but I think it would be worthwhile to wait and see what the original reviewers of [#90179](https://github.com/llvm/llvm-project/pull/90179) and https://github.com/llvm/llvm-project/pull/90214 think.

https://github.com/llvm/llvm-project/pull/92895