[clang] [llvm] [X86] Support apxf in attribute target (PR #184078)

[Mikołaj Piróg via cfe-commits]

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@@ -179,10 +179,15 @@ bool X86TargetInfo::initFeatureMap(
       continue;
     }
 
+    if (llvm::X86::expandAPXFeatures(Feature, getTriple(), UpdatedFeaturesVec))
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mikolaj-pirog wrote:

Attribute target supports negative features as well, testing shows an example of that

https://github.com/llvm/llvm-project/pull/184078