[llvm] [AMDGPU][GlobalIsel] RegBankLegalizeRules for amdgcn_s_quadmask (PR #202698)

[Chinmay Deshpande via llvm-commits]

chinmaydd wrote:

This was done by https://github.com/llvm/llvm-project/pull/201898, although there needs to be a fix implemented to clean up divergent rules

https://github.com/llvm/llvm-project/pull/202698