src: use NFPROTO_ constants

Resync netfilter.h from the latest kernel and make use of the new
NFPROTO_ constants that have been introduced.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
diff --git a/extensions/libxt_sctp.c b/extensions/libxt_sctp.c
index 5bd06a3..37a6423 100644
--- a/extensions/libxt_sctp.c
+++ b/extensions/libxt_sctp.c
@@ -510,7 +510,7 @@
 
 static struct xtables_match sctp_match = {
 	.name		= "sctp",
-	.family		= AF_INET,
+	.family		= NFPROTO_IPV4,
 	.version	= XTABLES_VERSION,
 	.size		= XT_ALIGN(sizeof(struct xt_sctp_info)),
 	.userspacesize	= XT_ALIGN(sizeof(struct xt_sctp_info)),
@@ -524,7 +524,7 @@
 
 static struct xtables_match sctp_match6 = {
 	.name		= "sctp",
-	.family		= AF_INET6,
+	.family		= NFPROTO_IPV6,
 	.version	= XTABLES_VERSION,
 	.size		= XT_ALIGN(sizeof(struct xt_sctp_info)),
 	.userspacesize	= XT_ALIGN(sizeof(struct xt_sctp_info)),