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

[Jonathan Thackray 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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jthackray wrote:

Done.

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