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

[Fangrui Song via llvm-commits]

MaskRay wrote:

> Forgetting compressed debug info for a minute, those LLD warnings are reproducible with:
> 
> ```
> $ cd linux
> $ make LLVM=1 ARCH=i386 -j128 -s defconfig all
> ```
> 
> The warnings are not observed at the commit before your change. Seems like a regression?

Thanks for testing this patch on the Linux kernel. However, I think the problem is in the Linux kernel, specifically, `arch/x86/include/asm/nospec-branch.h`.

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