[llvm] [AMDGPU]: Rewrite mbcnt_lo/mbcnt_hi to work item ID where applicable (PR #160496)

[Christudasan Devadasan via llvm-commits]

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@@ -0,0 +1,154 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 6
+; RUN: opt -S -mtriple amdgcn-unknown-amdhsa -mcpu=gfx1030 -passes=amdgpu-codegenprepare < %s | FileCheck %s
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cdevadas wrote:

```suggestion
; RUN: opt -S -mtriple=amdgcn-amd-amdhsa -mcpu=gfx1030 -passes=amdgpu-codegenprepare < %s | FileCheck %s
```

https://github.com/llvm/llvm-project/pull/160496