[lld] [ELF] --why-live: Skip symbol at index 0 and section symbols, handle .eh_frame symbols (PR #177099)

[Fangrui Song via llvm-commits]

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@@ -327,8 +327,13 @@ void MarkLive<ELFT, TrackWhyLive>::printWhyLive(Symbol *s) const {
 
     if (std::holds_alternative<Symbol *>(cur))
       printSymbol(std::get<Symbol *>(cur));
-    else
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MaskRay wrote:

Reverted

https://github.com/llvm/llvm-project/pull/177099