net, scsi/csgb4i: convert skb->transport_header into skb_transport_header(skb)

The change set of 1a37e412, "net: Use 16bits for *_headers fields
of struct skbuff" converted from sk_buff_data_t into 16bit integer.
So skb->tail needs to be converted to skb_tail_pointer(skb).

Found by inspection. Compile tested only.

Cc: Simon Horman <horms@verge.net.au>
Cc: Li RongQing <roy.qing.li@gmail.com>
Cc: linux-scsi@vger.kernel.org
Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
Acked-by: Simon Horman <horms@verge.net.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/scsi/cxgbi/cxgb4i/cxgb4i.c

@@ -358,7 +358,7 @@ static inline unsigned int calc_tx_flits_ofld(const struct sk_buff *skb)
 		return DIV_ROUND_UP(skb->len, 8);
 	flits = skb_transport_offset(skb) / 8;
 	cnt = skb_shinfo(skb)->nr_frags;
-	if (skb->tail != skb->transport_header)
+	if (skb_tail_pointer(skb) != skb_transport_header(skb))
 		cnt++;
 	return flits + sgl_len(cnt);
 }