[lld-macho] Make time-trace* options more permissive.

If either `time-trace-granularity` or `time-trace-file` is specified, then don't make users specify `-time-trace`.
It seems silly that I have to type all three options, eg, `-time-trace -time-trace-file=- -time-trace-granularity=...`.

Differential Revision: https://reviews.llvm.org/D100011