[llvm] [SimplifyCFG] Set branch weights when merging conditional store to address (PR #154841)

[Joel E. Denny via llvm-commits]

https://github.com/jdenny-ornl approved this pull request.

I have not fully digested the surrounding code, but this LGTM, other than the nits I pointed out.

https://github.com/llvm/llvm-project/pull/154841