[llvm] [AMDGPU][MC] Disallow op_sel in v_dot4 and v_dot8 with 4- or 8-bit packed data (PR #100485)

[Jun Wang via llvm-commits]

jwanggit86 wrote:

BTW, this is for issue [44257](https://github.com/llvm/llvm-project/issues/44257).

https://github.com/llvm/llvm-project/pull/100485