[clang] [clang][analyzer] Implement modeling of 'fputc' in the StdLibraryFunctionsChecker (PR #77435)

[Ben Shi via cfe-commits]

benshi001 wrote:

> I have already a patch to add these functions: #76979. The conditions for `fputc` are not the same, this can be clarified at the other patch.

I see. It would be better to close this PR, and supplement my parts in your PR.

https://github.com/llvm/llvm-project/pull/77435