[llvm] [AMDGPU] Restore non-buffer atomic tests lost in #93801 (PR #94978)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,45 @@
+; RUN: llc < %s -mtriple=amdgcn -mcpu=gfx1030 -verify-machineinstrs | FileCheck %s -check-prefixes=GCN,PREGFX12
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arsenm wrote:

Rename file to llvm.amdgcn.global.atomic.csub.ll 

https://github.com/llvm/llvm-project/pull/94978