cxgb4: add missing release on skb in uld_send()

In the implementation of uld_send(), the skb is consumed on all
execution paths except one. Release skb when returning NET_XMIT_DROP.
Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/chelsio/cxgb4/sge.c

@@ -2938,6 +2938,7 @@ static inline int uld_send(struct adapter *adap, struct sk_buff *skb,
 	txq_info = adap->sge.uld_txq_info[tx_uld_type];
 	if (unlikely(!txq_info)) {
 		WARN_ON(true);
+		kfree_skb(skb);
 		return NET_XMIT_DROP;
 	}