[llvm] [BOLT] Fix order of R_*_IRELATIVE in .rela.plt (PR #106515)

[via llvm-commits]

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@@ -899,7 +899,7 @@ bool Relocation::isIRelative(uint64_t Type) {
   case Triple::aarch64:
     return Type == ELF::R_AARCH64_IRELATIVE;
   case Triple::riscv64:
-    llvm_unreachable("not implemented");
+    return Type == ELF::R_RISCV_IRELATIVE;
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linsinan1995 wrote:

> Can we replace the whole function body with `return Type == getIRelative();`?

Some extensions may introduce new variants（[R_AARCH64_AUTH_[I]RELATIVE](https://github.com/ARM-software/abi-aa/blob/main/pauthabielf64/pauthabielf64.rst)）, but currently, BOLT has no plans to support them, so I think we can make this chang. Do you have any suggestions?

https://github.com/llvm/llvm-project/pull/106515