Store a Symbol for EntrySym.

This makes it impossible to forget to call repl on the SymbolBody.

llvm-svn: 266432
diff --git a/lld/ELF/MarkLive.cpp b/lld/ELF/MarkLive.cpp
index 4d0b08d..ade0dce 100644
--- a/lld/ELF/MarkLive.cpp
+++ b/lld/ELF/MarkLive.cpp
@@ -99,12 +99,13 @@
 
   auto MarkSymbol = [&](SymbolBody *Sym) {
     if (Sym)
-      if (auto *D = dyn_cast<DefinedRegular<ELFT>>(&Sym->repl()))
+      if (auto *D = dyn_cast<DefinedRegular<ELFT>>(Sym))
         Enqueue(D->Section);
   };
 
   // Add GC root symbols.
-  MarkSymbol(Config->EntrySym);
+  if (Config->EntrySym)
+    MarkSymbol(Config->EntrySym->Body);
   MarkSymbol(Symtab->find(Config->Init));
   MarkSymbol(Symtab->find(Config->Fini));
   for (StringRef S : Config->Undefined)