[UDP]: Use __skb_pull since we have checked it won't fail with pskb_may_pull

Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

net/ipv4/udp.c

···
 	 * transport header to point to ESP.  Keep UDP on the stack
 	 * for later.
 	 */
-	skb->h.raw = skb_pull(skb, len);
+	skb->h.raw = __skb_pull(skb, len);
 
 	/* modify the protocol (it's ESP!) */
 	iph->protocol = IPPROTO_ESP;