[CI] Fix triton wheel build (#87461)
If one to use auto-install llvm mechanism, somehow one ends us with
few unresovled symbols if build on manylinux image.
Workaround by installing llvm from OS repos.
Also, add an upload job, which is executed only on trunk
Fixes https://github.com/pytorch/torchdynamo/issues/1733
Pull Request resolved: https://github.com/pytorch/pytorch/pull/87461
Approved by: https://github.com/msaroufim
