[clang] [clang] check deduction consistency when partial ordering function templates (PR #100692)

[Matheus Izvekov via cfe-commits]

mizvekov wrote:

Yep, there is probably a macro somewhere guarding against GCC and possibly also c++ standards from C++17 up.
That should be replaced by a macro guarding for `__cpp_template_template_args <= 201611L` instead.

https://github.com/llvm/llvm-project/pull/100692