[llvm] [NFC][AMDGPU] Move image-atomic-attributes test to test/Assembler. (PR #76917)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,191 @@
+; RUN: opt -S -mtriple=amdgcn-unknown-unknown < %s | FileCheck -check-prefixes=CHECK %s
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arsenm wrote:

-check-prefixes=CHECK is the same as the default, can just drop it 

https://github.com/llvm/llvm-project/pull/76917