[clang] [Clang][AArch64] Use 'uint64_t*' for _arm_get_sme_state builtin. (PR #95982)

[Sander de Smalen via cfe-commits]

sdesmalen-arm wrote:

I've tested this change locally, but wasn't sure how to write a test for it.

https://github.com/llvm/llvm-project/pull/95982