[lld] [lld][LoongArch] Relax R_LARCH_PCALA_HI20 and R_LARCH_PCALA_LO12 (PR #112696)

[Lu Weining via llvm-commits]

https://github.com/SixWeining commented:

Basically it looks good to me. But I'd like to know how did you test the relaxation functionality? For example, use gcc(with relax enabled) + lld to build some programs?

@MQ-mengqing's do you have any futher comments?

https://github.com/llvm/llvm-project/pull/112696