[clang] [AArch64][llvm] Add support for new vcvt* intrinsics (PR #163572)

[Jonathan Thackray via cfe-commits]

jthackray wrote:

> Oh, also, we probably want a release note for this.

Thanks. Our team is adding quite a few new intrinsics soon (I've got another intrinsics patch soon I'm working on) so I'll ensure they're all documented.

https://github.com/llvm/llvm-project/pull/163572