[llvm] r204404 - Remove llvm-mc's disable-cfi option.

[Tim Northover]

Hi Rafael,

> Remove llvm-mc's disable-cfi option.
>
> It was dead.

Isn't this actually theoretically useful for testing the bytes we emit
from .cfi directives? In the absence of functional llvm-dwarfdump
frame info the output of -disable-cfi is much friendlier than
"llvm-readobj -section-data".

OK, so we don't appear to actually do that yet. But I'd be up for
putting together a few tests.

Cheers.

Tim.