[thrift] fix _thrift for inheriting services

Summary: obviously Iain's fault


git-svn-id: https://svn.apache.org/repos/asf/incubator/thrift/trunk@665272 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/compiler/cpp/src/generate/t_erl_generator.cc b/compiler/cpp/src/generate/t_erl_generator.cc
index 8f020bf..9c093d7 100644
--- a/compiler/cpp/src/generate/t_erl_generator.cc
+++ b/compiler/cpp/src/generate/t_erl_generator.cc
@@ -890,7 +890,7 @@
 
   indent(f_service_) << "  _ -> % unknown function" << endl;
   if (tservice->get_extends() != NULL) {
-    indent(f_service_) << "    " << extends << ":proc(Name,_Type,Seqid,HandlerModule, Iprot, Oprot)" << endl;
+    indent(f_service_) << "    " << extends << "_thrift:proc(Name,_Type,Seqid,HandlerModule, Iprot, Oprot)" << endl;
   } else {
     f_service_ <<
       indent() << "    ?R1(Iprot, skip, ?tType_STRUCT)," << endl <<