[llvm] [clang] [Clang][SME2] Add builtins for moving multi-vectors to/from ZA (PR #71191)

[David Sherwood via cfe-commits]

https://github.com/david-arm approved this pull request.

LGTM! I had one minor comment, but I won't hold up the patch for it.

https://github.com/llvm/llvm-project/pull/71191