[clang] [clang] Implement __builtin_stdc_rotate_left, __builtin_stdc_rotate_right (PR #160259)

[Erich Keane via cfe-commits]

erichkeane wrote:

@efriedma-quic is the only one I can see that has open comments?  I'd give him time on that, otherwise I would suspect this could be merged.

https://github.com/llvm/llvm-project/pull/160259