[lld] [ELF] Support relocatable files using CREL (PR #98115)

[Peter Smith via llvm-commits]

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@@ -84,6 +84,7 @@ class InputFile {
     assert(fileKind == ObjKind || fileKind == BinaryKind);
     return sections;
   }
+  void setSection(size_t i, InputSectionBase *s) { sections[i] = s; }
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smithp35 wrote:

Given that we probably don't want to encourage heavy use of this function as it makes sections publically writeable. 

Could it be worth calling it `cacheDecodedCrel` instead?

https://github.com/llvm/llvm-project/pull/98115