[clang] [llvm] Revert the clang SSAF orchestrator/driver stack (PR #232274)

[Balázs Benics via cfe-commits]

steakhal wrote:

I plan to merge the revert stack without formal approval - to not block on any of you.
I'll merge it as soon as the pre-merge checks are green on it.

https://github.com/llvm/llvm-project/pull/232274