ipv6: rename datagram_send_ctl and datagram_recv_ctl

The datagram_*_ctl functions in net/ipv6/datagram.c are IPv6-specific.  Since
datagram_send_ctl is publicly exported it should be appropriately named to
reflect the fact that it's for IPv6 only.

Signed-off-by: Tom Parkin <tparkin@katalix.com>
Signed-off-by: James Chapman <jchapman@katalix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
index dfaa29b..fb08329 100644
--- a/net/ipv6/udp.c
+++ b/net/ipv6/udp.c
@@ -443,7 +443,7 @@
 			ip_cmsg_recv(msg, skb);
 	} else {
 		if (np->rxopt.all)
-			datagram_recv_ctl(sk, msg, skb);
+			ip6_datagram_recv_ctl(sk, msg, skb);
 	}
 
 	err = copied;
@@ -1153,8 +1153,8 @@
 		memset(opt, 0, sizeof(struct ipv6_txoptions));
 		opt->tot_len = sizeof(*opt);
 
-		err = datagram_send_ctl(sock_net(sk), sk, msg, &fl6, opt,
-					&hlimit, &tclass, &dontfrag);
+		err = ip6_datagram_send_ctl(sock_net(sk), sk, msg, &fl6, opt,
+					    &hlimit, &tclass, &dontfrag);
 		if (err < 0) {
 			fl6_sock_release(flowlabel);
 			return err;