[clang] [clang] Fix the local parameter of void type inside the `Requires` expression. (PR #109831)

[Matheus Izvekov via cfe-commits]

mizvekov wrote:

> I'm wondering what level of granularity we should aim for when reusing the current implementation in `GetTypeForDeclarator`?

You can perhaps extract just the parts that are common between both use cases into a separate function, or another possible approach would be to reuse the whole thing, but then add an extra mode parameter which turns off some checks for the requires local parameters.

https://github.com/llvm/llvm-project/pull/109831