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

[Matheus Izvekov via cfe-commits]

mizvekov wrote:

@lukel97 

If you can reduce, I would appreciate it.

You can also post here an unreduced pre-processed unit which compiles fine with clang before this patch.

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