[compiler-rt] Revert "[compiler-rt][aarch64] Add SME ABI support routines." (PR #68875)

[Sander de Smalen via llvm-commits]

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

Thanks for letting me know, I'll investigate it. Happy to have it reverted in the meantime.

https://github.com/llvm/llvm-project/pull/68875