[clang] [llvm] [AArch64] Add a check for invalid default features (PR #104435)

[Ahmed Bougacha via cfe-commits]

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@@ -892,7 +905,7 @@ def ProcessorFeatures {
                                     FeatureComplxNum, FeatureCRC, FeatureJS,
                                     FeatureLSE, FeaturePAuth, FeatureFPAC,
                                     FeatureRAS, FeatureRCPC, FeatureRDM,
-                                    FeatureDotProd, FeatureMatMulInt8];
+                                    FeatureDotProd, FeatureMatMulInt8, FeatureSSBS];
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ahmedbougacha wrote:

AppleM4 actually does not have SSBS, unlike the previous ones

https://github.com/llvm/llvm-project/pull/104435