[clang] [clang-format] Support of TableGen formatting. (PR #76059)

[Emilia Kond via cfe-commits]

https://github.com/rymiel commented:

Hi, this is quite a big patch. I had a very quick look and noticed a few nit-picky thingy, mostly about formatting or naming and whatnot, mostly minor things.
However since I've never used tablegen, I'm not sure if I can actually review any of the logic in here, but I'll try to have another look later

https://github.com/llvm/llvm-project/pull/76059