[clang] [Clang][Driver] Add new flags to control machine instruction verification (PR #70282)

[Matheus Izvekov via cfe-commits]

mizvekov wrote:

I don't disagree that if we stop at this step, then the flag doesn't buy much. But it would be worthwhile if we ever implemented LTO integration or implemented a lightweight machine verification which runs the pass 1 or 2 times, which would work similarly to the IR verification flag.

So shall we put this MR to sleep until we have that, or otherwise abandon this effort?
Either way works for me.

https://github.com/llvm/llvm-project/pull/70282