[llvm] [OpenMP] Replace AMDGPU fences with generic scoped fences (PR #119619)

[Jan Patrick Lehr via llvm-commits]

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@@ -26,6 +26,14 @@ enum OrderingTy {
   seq_cst = __ATOMIC_SEQ_CST,
 };
 
+enum ScopeTy {
+  system = __MEMORY_SCOPE_SYSTEM,
+  device_ = __MEMORY_SCOPE_DEVICE,
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jplehr wrote:

Is this on purpose with `_` to not conflict with something?

https://github.com/llvm/llvm-project/pull/119619