[clang] add more function annotations to clang python bindings (PR #193304)

[Jannick Kremer via cfe-commits]

DeinAlptraum wrote:

On first glance, this looks mostly good, with a few minor mistakes.

That said, it's also mostly overlapping with https://github.com/llvm/llvm-project/pull/78114 
What do you think we should do here @Endilll 

https://github.com/llvm/llvm-project/pull/193304