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/libip6t_hl.c b/extensions/libip6t_hl.c
index b895e36..1046b2e 100644
--- a/extensions/libip6t_hl.c
+++ b/extensions/libip6t_hl.c
@@ -127,7 +127,7 @@
 static struct xtables_match hl_mt6_reg = {
 	.name          = "hl",
 	.version       = XTABLES_VERSION,
-	.family        = PF_INET6,
+	.family        = NFPROTO_IPV6,
 	.size          = XT_ALIGN(sizeof(struct ip6t_hl_info)),
 	.userspacesize = XT_ALIGN(sizeof(struct ip6t_hl_info)),
 	.help          = hl_help,