net/sched: remove unneeded NULL check

There is no need to check "s".  nla_data() doesn't return NULL.  Also we
already dereferenced "s" at this point so it would have oopsed ealier if
it were NULL.
Signed-off-by: NDan Carpenter <error27@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/sched/sch_api.c

@@ -360,7 +360,7 @@ static struct qdisc_size_table *qdisc_get_stab(struct nlattr *opt)
 		tsize = nla_len(tb[TCA_STAB_DATA]) / sizeof(u16);
 	}
 
-	if (!s || tsize != s->tsize || (!tab && tsize > 0))
+	if (tsize != s->tsize || (!tab && tsize > 0))
 		return ERR_PTR(-EINVAL);
 
 	spin_lock(&qdisc_stab_lock);