[llvm] [llvm][Support] Add YAMLGenerateSchema for producing YAML schemas (PR #133284)

[Timur Golubovich via llvm-commits]

tgs-sc wrote:

@kazutakahirata, Hi! I saw that you have recently commited to this area (special thanks that you made clang-format). Probably you can take a look at these changes?

https://github.com/llvm/llvm-project/pull/133284