[llvm] [DA] Require `nsw` for AddRecs in the WeakCrossing SIV test (PR #185041)

[Ehsan Amiri via llvm-commits]

amehsan wrote:

there was a change in testcases after rebasing. I am merging anyways, but feel free to leave a post-merge comment if you have a comment.

https://github.com/llvm/llvm-project/pull/185041