new helper: skb_copy_and_csum_datagram_msg()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index dbc0b04..7cfb5d7 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -428,7 +428,7 @@
 		err = skb_copy_datagram_msg(skb, sizeof(struct udphdr),
 					    msg, copied);
 	else {
-		err = skb_copy_and_csum_datagram_iovec(skb, sizeof(struct udphdr), msg->msg_iov);
+		err = skb_copy_and_csum_datagram_msg(skb, sizeof(struct udphdr), msg);
 		if (err == -EINVAL)
 			goto csum_copy_err;
 	}