[clang] Mechanically port bulk of x86 builtins to TableGen (PR #120831)

[Chandler Carruth via cfe-commits]

chandlerc wrote:

Thanks, merging! I've put the script here for posterity: https://gist.github.com/chandlerc/de807ea073beac351f87c660e1d4b7a0

https://github.com/llvm/llvm-project/pull/120831