[llvm] Add amdgpu paths to CODEOWNERS (PR #65229)

[Matt Arsenault via llvm-commits]

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@@ -459,6 +459,10 @@ utils/bazel/llvm-project-overlay/libc/** @llvm/pr-subscribers-libc
 /clang/lib/CodeGen/Targets/AArch64.cpp @llvm/pr-subscribers-AArch64
 /clang/include/clang/Basic/BuiltinsAArch64* @llvm/pr-subscribers-AArch64
 
+# AMDGPU
+**/*AMDGPU* @llvm/pr-subscribers-amdgpu
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arsenm wrote:

Test directories should probably be covered. I'm not too worried about picking up extra tests 

https://github.com/llvm/llvm-project/pull/65229