MXS-2246 Remove duplicate info in SERVICE and Service

Both of them contained fields for the service and router names.
Now the names are in SERVICE and they must be accessed via member
function.

server/modules/authenticator/PAM/PAMAuth/pam_instance.cc

@@ -220,7 +220,7 @@ int PamInstance::load_users(SERVICE* service)
                         mxb_assert(mysql_num_fields(res) == PAM_USERS_QUERY_NUM_FIELDS);
                         MXS_NOTICE("Loaded %llu users for service %s.",
                                    mysql_num_rows(res),
-                                   service->name);
+                                   service->name());
                         MYSQL_ROW row;
                         while ((row = mysql_fetch_row(res)))
                         {