IB/rxe: Don't check for null ptr in send()

pkt->qp was already dereferenced earlier in the function.

Fixes Smatch complaint:
drivers/infiniband/sw/rxe/rxe_net.c:458 send()
	 warn: variable dereferenced before check 'pkt->qp' (see line 441)
Signed-off-by: Andrew Boyer <andrew.boyer@dell.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/sw/rxe/rxe_net.c

@@ -459,7 +459,6 @@ static int send(struct rxe_dev *rxe, struct rxe_pkt_info *pkt,
 		return -EAGAIN;
 	}
 
-	if (pkt->qp)
 	atomic_inc(&pkt->qp->skb_out);
 	kfree_skb(skb);