[llvm] [AMDGPU] fix SIPeepholeSDWA optimization for fp16 (PR #109395)

[Pankaj Dwivedi via llvm-commits]

PankajDwivedi-25 wrote:

> Could #106920 be related?

yeah, it talks about the same pass. but that is not the case here. 

https://github.com/llvm/llvm-project/pull/109395