[llvm] [MemCpyOpt] Allow memcpy elision for non-noalias arguments (PR #107860)

[via llvm-commits]

https://github.com/DianQK approved this pull request.

LGTM. Thanks!

Could you update the comment for this function? Maybe just modify it to: 

```
/// 1. The memcpy dst is neither modified during the call nor captured by the
/// call. (e.g. readonly, noalias, nocapture attributes on call-site.)
```

https://github.com/llvm/llvm-project/pull/107860