[llvm] [AMDGPU] Remove dead check lines from tests (NFC) (PR #228002)

[Jay Foad via llvm-commits]

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@@ -2284,7 +2284,6 @@ define i8 @test_atomicrmw_usub_cond_i8_flat_agent_align2(ptr %ptr, i8 %value) {
 ; R600-NEXT:    [[EXTRACTED3:%.*]] = trunc i32 [[SHIFTED2]] to i8
 ; R600-NEXT:    ret i8 [[EXTRACTED3]]
 ;
-; R600NEXT:    [[PTRLSB:%.*]] = and i32 [[TMP1]], 3
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jayfoad wrote:

This is fine.

https://github.com/llvm/llvm-project/pull/228002