[lld] [RISCV][LLD] Add RISCV zcmt optimise in linker relaxation (PR #77884)

[Kito Cheng via llvm-commits]

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@@ -838,9 +893,11 @@ void elf::riscvFinalizeRelax(int passes) {
             skip = 4;
             write32le(p, aux.writes[writesIdx++]);
             break;
+          case R_RISCV_64:
+            break;
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kito-cheng wrote:

Does it used when generating `.riscv.jvt`? Maybe add some comment?

https://github.com/llvm/llvm-project/pull/77884