netlink: implement nla_get_in_addr and nla_get_in6_addr

Those are counterparts to nla_put_in_addr and nla_put_in6_addr.

Signed-off-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/l2tp/l2tp_netlink.c b/net/l2tp/l2tp_netlink.c
index a4f78d3..9e13c2f 100644
--- a/net/l2tp/l2tp_netlink.c
+++ b/net/l2tp/l2tp_netlink.c
@@ -205,9 +205,9 @@
 #endif
 		if (info->attrs[L2TP_ATTR_IP_SADDR] &&
 		    info->attrs[L2TP_ATTR_IP_DADDR]) {
-			cfg.local_ip.s_addr = nla_get_be32(
+			cfg.local_ip.s_addr = nla_get_in_addr(
 				info->attrs[L2TP_ATTR_IP_SADDR]);
-			cfg.peer_ip.s_addr = nla_get_be32(
+			cfg.peer_ip.s_addr = nla_get_in_addr(
 				info->attrs[L2TP_ATTR_IP_DADDR]);
 		} else {
 			ret = -EINVAL;