[lld] [llvm] [LoongArch] Use R_LARCH_ALIGN with section symbol (PR #84741)

[Lu Weining via llvm-commits]

https://github.com/SixWeining approved this pull request.

I'd accept this change and cherry-pick to 18.x to keep compatible with gcc/binutils. (18.1.4 will be released soon. We don't have too much time.)
For the generic improvement mentioned above, I think it can be done later.

https://github.com/llvm/llvm-project/pull/84741