[lld] [ELF] Support relocatable files using CREL (PR #98115)

[Fangrui Song via llvm-commits]

MaskRay wrote:

There is still time to include this patch before  the LLVM 19.1-rc2 release on August 6th.
However, introducing new features after that could be challenging.
The 19.1 release will showcase the impressive relocatable size reduction to the wider ELF OS community.


https://github.com/llvm/llvm-project/pull/98115