[llvm] [AMDGPU] Convert ds_bpermute/wave_shuffle XOR patterns to DPP row_xmask and permlanex16 (PR #194565)

[Matt Arsenault via llvm-commits]

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arsenm wrote:

```suggestion
        ShiftAmt == 2 && (XorConst & 3) == 0 && isThreadID(ST, Tid))
```

https://github.com/llvm/llvm-project/pull/194565