[clang] [analyzer] Simplify SVal for simple NonLoc->Loc casts (PR #66463)

[Balazs Benics via cfe-commits]

https://github.com/steakhal commented:

I like it. Thanks!
This is pretty much good to go, but let's have a short discussion first.

https://github.com/llvm/llvm-project/pull/66463