[clang] [analyzer] Make pointer/null comparison commutative for addresses of fields of symbolic regions (PR #209875)

[Balázs Benics via cfe-commits]

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

IDK what's the force push for. It didn't seem complicated to me.
Let's merge this.

https://github.com/llvm/llvm-project/pull/209875