[llvm] [AMDGPU] Allow negative offsets in scratch instructions (PR #166979)

[Matt Arsenault via llvm-commits]

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@@ -334,12 +334,6 @@ def FeatureFlatSegmentOffsetBug : SubtargetFeature<"flat-segment-offset-bug",
   "GFX10 bug where inst_offset is ignored when flat instructions access global memory"
 >;
 
-def FeatureNegativeScratchOffsetBug : SubtargetFeature<"negative-scratch-offset-bug",
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arsenm wrote:

I have very low confidence this is proof that the bug does not exist, and is more a sign we need to write targeted unit tests for this 

https://github.com/llvm/llvm-project/pull/166979