Fix ICE while updating inliner summary

[Jan Hubicka]

Hi,
this patch fix ICE seen when LTO optimizing clang.

Bootstrapped/regtested x86_64-linux.

        * ipa.c (walk_polymorphic_call_targets): Fix updating of overall
        summary.
Index: ipa.c
===================================================================
--- ipa.c       (revision 279724)
+++ ipa.c       (working copy)
@@ -244,7 +244,8 @@ walk_polymorphic_call_targets (hash_set<
            }
          edge = edge->make_direct (target);
          if (ipa_fn_summaries)
-           ipa_update_overall_fn_summary (node);
+           ipa_update_overall_fn_summary (node->inlined_to
+                                          ? node->inlined_to : node);
          else if (edge->call_stmt)
            edge->redirect_call_stmt_to_callee ();
        }