[lld-macho] Specify the complete set of command-line options for ld64
This is a complete Options.td compiled from ld(1) dated 2018-03-07 and
cross checked with ld64 source code version 512.4 dated 2018-03-18.
This is the first in a series of diffs for argument handling. Follow-ups
will include switch cases for all the new instances of OPT_foo, and
parsing/validation of arguments attached to options, e.g., more code
akin to OPT_platform_version and associated parsePlatformVersion().
Reviewed By: smeenai
Differential Revision: https://reviews.llvm.org/D80582