[clang] [compiler-rt] [llvm] [FMV][AArch64] Add feature CSSC and detect on linux platform. (PR #132727)

[Alexandros Lamprineas via llvm-commits]

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@@ -33,7 +33,7 @@ enum CPUFeatures {
   FEAT_FP,
   FEAT_SIMD,
   FEAT_CRC,
-  RESERVED_FEAT_SHA1, // previously used and now ABI legacy
+  FEAT_CSSC,
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labrinea wrote:

Yeap, we only need to make sure GNU is doing the same cc @Wilco1

https://github.com/llvm/llvm-project/pull/132727