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

[via llvm-commits]

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@@ -63,6 +76,7 @@ enum Reg {
   R_ZERO = 0,
   R_RA = 1,
   R_TP = 2,
+  R_A0 = 4,
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ywgrit wrote:

> Seems it is not used by current patch.

Yes, thanks for remainding.
Because the code of this pr is split from a complete relaxation patch, there may be partially unused code. I will check the code of this pr again as soon as possible.

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