[llvm] [llvm-size] Add --exclude-pagezero option for Mach-O to exclude __PAGEZERO size. (PR #159574)

[James Henderson via llvm-commits]

https://github.com/jh7370 requested changes to this pull request.

The documentation still needs updating, as stated in my earlier comment.

Also, the test only covers the LC_SEGMENT_64 case, but you've modified both that and the LC_SEGMENT path.

https://github.com/llvm/llvm-project/pull/159574