[clang] [clang][analyzer] Fix #embed crash (PR #107764)

[Donát Nagy via cfe-commits]

https://github.com/NagyDonat commented:

LGTM, there is no reason to crash on `#embed`.

I think it would be nice to have a few testcases that show the behavior of the analyzer around `#embed`:
- Can we produce bug reports if there is an (unrelated) `#embed` expression on the execution path? Or do we abort the analysis there?
- If the analysis is not aborted, then how do we represent the contents of a memory region that's initialized by `#embed`? Is it `UnknownVal`? Or `UndefinedVal` (that may be problematic)?

https://github.com/llvm/llvm-project/pull/107764