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/Writer.cpp b/lld/ELF/Writer.cpp
index c942b5d..ee1d32b 100644
--- a/lld/ELF/Writer.cpp
+++ b/lld/ELF/Writer.cpp
@@ -1634,8 +1634,8 @@
 }
 
 template <class ELFT> static typename ELFT::uint getEntryAddr() {
-  if (SymbolBody *B = Config->EntrySym)
-    return B->repl().getVA<ELFT>();
+  if (Symbol *S = Config->EntrySym)
+    return S->Body->getVA<ELFT>();
   if (Config->EntryAddr != uint64_t(-1))
     return Config->EntryAddr;
   return 0;