[clang] [llvm] [AArch64] Reduce +sve2-aes to an alias of +sve-aes+sve2 (PR #114293)

[via cfe-commits]

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@@ -369,9 +369,12 @@ def FeatureSVE2 : ExtensionWithMArch<"sve2", "SVE2", "FEAT_SVE2",
   "Enable Scalable Vector Extension 2 (SVE2) instructions",
   [FeatureSVE, FeatureUseScalarIncVL]>;
 
-def FeatureSVE2AES : ExtensionWithMArch<"sve2-aes", "SVE2AES",
+def FeatureSVEAES : ExtensionWithMArch<"sve-aes", "SVEAES",
   "FEAT_SVE_AES, FEAT_SVE_PMULL128",
-  "Enable AES SVE2 instructions", [FeatureSVE2, FeatureAES]>;
+  "Enable SVE AES and 128-bit PMULL instructions", [FeatureAES]>;
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SpencerAbson wrote:

I'm referring to the quadword variants of [PMULLB/PMULLT](https://developer.arm.com/documentation/ddi0602/2024-09/SVE-Instructions/PMULLB--Polynomial-multiply-long--bottom--) here. Perhaps I should change this to "Enable SVE AES and 128-bit elment SVE PMULL instructions".

https://github.com/llvm/llvm-project/pull/114293