[lld] [ELF] -r --compress-debug-sections: update addends for .debug_* sections relocated by REL (PR #66804)

[Peter Smith via llvm-commits]

https://github.com/smithp35 commented:

To make sure I understand the change:

* relocateNonAlloc now does all the work that relocateNonAllocForRelocateble so we can remove it.
* we now no longer need to copy relocations from non SHF_ALLOC sections as relocateNonAlloc processes the raw relocations like copyRelocations() does.

If the above is correct, I got a bit confused by the comment, but otherwise LGTM.

https://github.com/llvm/llvm-project/pull/66804