[llvm] [AMDGPU] Using feature to define vmem cacheline size (PR #207884)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,213 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 6
+; RUN: opt -mtriple=amdgcn -mcpu=gfx1250 -passes=loop-data-prefetch -S < %s | FileCheck %s --check-prefix=GFX12,GFX1250
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arsenm wrote:

```suggestion
; RUN: opt -mtriple=amdgpu12.50 -passes=loop-data-prefetch -S < %s | FileCheck %s --check-prefix=GFX12,GFX1250
```

Convert these to new amdgpu triples

https://github.com/llvm/llvm-project/pull/207884