[clang] Reapply "[analyzer] Fix false positive in strchr/strrchr with constant args" (PR #212124)

[Ulrich Weigand via cfe-commits]

uweigand wrote:

But we support Intel as target triple, that's just a normal cross-compile.   The problem is if something in the compiler (accidentally) depends on the host endianness.

https://github.com/llvm/llvm-project/pull/212124