Don't notify about missing function objects/functors

This was correct in vanilla, but in our case it's totally normal to miss
some functors and there's no need to nag about this in the log.

This also fixes FPS drop in Mixed configuration after #1751 merge due to BIG amount of logging about missing functors

src/xrScriptEngine/script_engine.cpp

@@ -1125,11 +1125,11 @@ bool CScriptEngine::function_object(LPCSTR function_to_call, luabind::object& ob
     {
         pstr file_name = strchr(name_space, '.');
         if (!file_name)
-            process_file(name_space);
+            process_file_if_exists(name_space, false);
         else
         {
             *file_name = 0;
-            process_file(name_space);
+            process_file_if_exists(name_space, false);
             *file_name = '.';
         }
     }