[clang] Bulk port 64-bit x86 builtins to TableGen (PR #121043)

[Chandler Carruth via cfe-commits]

chandlerc wrote:

Updated to rebase on top-of-tree with #120831 merged. Re-ran all the scripts to verify things.

Using a variation on the command from my [comment](https://github.com/llvm/llvm-project/pull/120831#discussion_r1903059479) on the other PR:

```fish
diff -u (rg '^TARGET' BuiltinsX86_64.def | sd ' +' ' ' | sd ',([X"])' ', $1' | sort | psub)  (rg '^TARGET' dev/tools/clang/include/clang/Basic/BuiltinsX86_64.inc | sort | psub)
```

I got the following diffs due to `LLi` becoming `Oi`, which again seem pretty reasonable: https://gist.github.com/chandlerc/03a29633e2e2726ec0fec33fd8e4e8ac

I guess let me know if I need to special case `usermsr` to exclude it from OpenCL?

https://github.com/llvm/llvm-project/pull/121043