[llvm] r212615 - Generic: add range-adapter for option parsing.

[Tim Northover]

> FYI: we do have a make_range function that can be used to simplify the
> range expression here:
>
>   return make_range(filtered_begin(ld0, ld1, ld2), filtered_range());

Oh, thanks. I didn't know about that. Committed in r212641.

Cheers.

Tim.