[lld] [lld-macho][NFC] Refactor insertions into inputSections (PR #85692)

[via llvm-commits]

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@@ -369,6 +369,7 @@ constexpr const char addrSig[] = "__llvm_addrsig";
 
 } // namespace section_names
 
+void addInputSection(InputSection *inputSection);
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alx32 wrote:

Added docs to function body. 

https://github.com/llvm/llvm-project/pull/85692