Demangle symbols when including them in error messages.

llvm-svn: 257647
diff --git a/lld/ELF/Driver.cpp b/lld/ELF/Driver.cpp
index f00d978..25b938b 100644
--- a/lld/ELF/Driver.cpp
+++ b/lld/ELF/Driver.cpp
@@ -185,6 +185,7 @@
 
   Config->AllowMultipleDefinition = Args.hasArg(OPT_allow_multiple_definition);
   Config->Bsymbolic = Args.hasArg(OPT_Bsymbolic);
+  Config->Demangle = !Args.hasArg(OPT_no_demangle);
   Config->DiscardAll = Args.hasArg(OPT_discard_all);
   Config->DiscardLocals = Args.hasArg(OPT_discard_locals);
   Config->DiscardNone = Args.hasArg(OPT_discard_none);