[llvm] [llvm-objcopy] Always update indirectsymoff in MachO (PR #117726)

[Richard Dzenis via llvm-commits]

RIscRIpt wrote:

> Please add/update a test case to cover this behaviour.

I find it difficult generating a MachO reliably so that all the nuances are preserved to observe the desired effect.

I try to investigate how to craft such MachO if reviewers think I should add a regression test.

> Please could you add some reviewers who have been involved in modifying the Mach-O code in llvm-objcopy, either officially as reviewers, or by pinging them in the comments, depending on whether you have commit access or not.

As far as I can see @nuta who was the author of this file was not contributing to llvm-project lately (as per `git log --author=nuta`), so I've added people who were reviewing his changes.

https://github.com/llvm/llvm-project/pull/117726