wimax/i2400m: remove open-coded skb_cow_head.

Signed-off-by: NFrancois Romieu <romieu@fr.zoreil.com>
Cc: Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/wimax/i2400m/netdev.c

@@ -374,8 +374,7 @@ netdev_tx_t i2400m_hard_start_xmit(struct sk_buff *skb,
 
 	d_fnstart(3, dev, "(skb %p net_dev %p)\n", skb, net_dev);
 
-	if (skb_header_cloned(skb) && 
-	    pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
+	if (skb_cow_head(skb, 0))
 		goto drop;
 
 	if (i2400m->state == I2400M_SS_IDLE)