[clang] [clang][analyzer] Restrict 'fopen' modeling to POSIX versions in SimpleStreamChecker (PR #72016)

[Balázs Kéri via cfe-commits]

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

The change is OK, automated tests show a failure but it is in an unrelated test.

https://github.com/llvm/llvm-project/pull/72016