[clang] [Clang] Disallow explicit object parameters in more contexts (PR #89078)

[via cfe-commits]

Sirraide wrote:

> Note this PR is related to
> https://github.com/llvm/llvm-project/pull/88974/files

That’s pr covers a different code path from what I can tell though (unless requires expressions are also modelled as function declarators, I’m honestly not sure about that one).

It also reminds me that this still needs a release note.

https://github.com/llvm/llvm-project/pull/89078