[clang] [NFC][AArch64] Add relnote saying SVE2.1 and SME2.1 now fully implemented by ACLE (PR #122705)

[via cfe-commits]

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@@ -1045,6 +1045,9 @@ X86 Support
 Arm and AArch64 Support
 ^^^^^^^^^^^^^^^^^^^^^^^
 
+- Support for SVE2.1 and SME2.1 using the Arm C Language Extensions (ACLE) is
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CarolineConcatto wrote:

I am not sure if "using" is the best work, maybe "according to".
I looked on how Momchil did for BitInt:
https://github.com/llvm/llvm-project/pull/101521/files
Maybe :
lmplementation of SVE2.1 and SME2.1 in accordance with the Arm C Language Extensions (ACLE) is now available


https://github.com/llvm/llvm-project/pull/122705