[llvm] [AMDGPU] Calc IsVALU correctly during UADDO/USUBO selection (PR #159814)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,26 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 6
+; RUN: llc -mtriple=amdgcn-amd-amdpal -stop-after=amdgpu-isel < %s | FileCheck -check-prefixes=GCN-ISEL %s
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arsenm wrote:

```suggestion
; RUN: llc -mtriple=amdgcn-amd-amdpal -mcpu=gfx900 -stop-after=amdgpu-isel < %s | FileCheck -check-prefixes=GCN-ISEL %s
```

Use same subtarget for both cases 

https://github.com/llvm/llvm-project/pull/159814