[re-land][lld-macho] Fix min version check

[re-land][lld-macho] Fix min version check

We had got it backwards... the minimum version of the target
should be higher than the min version of the object files, presumably
since new platforms are backwards-compatible with older formats.

Fixes PR50078.

The original commit (aa05439c9cde) broke many tests that had inputs too
new for our target platform (10.0). This commit changes the inputs to
target 10.0, which was the simpler thing to do, but we should really
just have our lit.local.cfg default to targeting 10.15... we're not
likely to ever have proper support for the older versions anyway. I will
follow up with a change to that effect.

Differential Revision: https://reviews.llvm.org/D101114