[clang] [analyzer] Never create Regions wrapping reference TypedValueRegions (NFCI) (PR #118096)

[Donát Nagy via cfe-commits]

NagyDonat wrote:

> The second is, how can we end up with such subregions. I think the only way is by field regions. If we had something that I missed, the assert would catch it.

Quick guesses: can we form a base or derived object subregion from them? Is there some hacky pathway where we create an element region to represent something that's not a real element access but something similar? (`ElementRegion` may mean 53 different things, I wouldn't be surprised if it can appear somehow...)

https://github.com/llvm/llvm-project/pull/118096