[lld] [ELF] Parallelize version script and dynamic list matching (PR #223208)

[Fangrui Song via llvm-commits]

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@@ -127,19 +128,7 @@ static std::string demangleForVersion(StringRef name) {
   return s;
 }
 
-// Initialize demangledSyms with a map from demangled symbols to symbol
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MaskRay wrote:

Simplified this comment originally from 2016. I think it's mostly stale.

https://github.com/llvm/llvm-project/pull/223208