[obj2yaml][yaml2obj] Adding enumFallback for MachO load commands

This adds support for handling unknown load commands, and a bogus_load_command tests.

Unknown or unsupported load commands can be specified in YAML by their hex value.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@270239 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed