[clang] [Analyzer][CFG] Correctly handle rebuilt default arg and default init expression (PR #117437)

[via cfe-commits]

https://github.com/cor3ntin requested changes to this pull request.

I'd like more time to think about this change and discuss it with @AaronBallman / @erichkeane 

https://github.com/llvm/llvm-project/pull/117437