[clang] [clang-repl] Extend the C support. (PR #89804)

[Vassil Vassilev via cfe-commits]

vgvassilev wrote:

@hokein, ah, that's annoying. Can you provide the entire proprocessed file that does not work? I'd like to bisect and debug.

https://github.com/llvm/llvm-project/pull/89804