message: Add missing break from trace-cmd process_arg_token
diff: @@ -3182,6 +3182,7 @@ process_arg_token(struct event_format *event, struct print_arg *arg,
  type = process_paren(event, arg, &token);
  break;
  }
  + break;
  case EVENT_OP:
  /* handle single ops */
  arg->type = PRINT_OP;
  