message: Fix trace-cmd buffer overrun
  When val is (1LL << 63), "-9223372036854775808" needs 21 bytes
  due to the negative sign.
diff: @@ -2509,7 +2509,7 @@ static int arg_num_eval(struct print_arg *arg, long long *val)
  static char *arg_eval (struct print_arg *arg)
  {
  long long val;
  - static char buf[20];
  + static char buf[32];
  switch (arg->type) {
  case PRINT_ATOM:
  