[clang] [compiler-rt] -fsanitize=alignment: check memcpy/memmove arguments (PR #67766)

[Antoine Pitrou via cfe-commits]

pitrou wrote:

Judging by the list of notifications at the bottom of this PR, this does seem to have hit a number of projects (including [our own](https://github.com/apache/arrow/issues/44372)).

https://github.com/llvm/llvm-project/pull/67766