[NETFILTER]: Fix IP_NF_CONNTRACK_NETLINK dependency

When NAT is built as a module, ip_conntrack_netlink can not be linked
statically.
Signed-off-by: NPatrick McHardy <kaber@trash.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv4/netfilter/Kconfig

@@ -69,6 +69,7 @@ config IP_NF_CONNTRACK_NETLINK
 	tristate 'Connection tracking netlink interface (EXPERIMENTAL)'
 	depends on EXPERIMENTAL && IP_NF_CONNTRACK && NETFILTER_NETLINK
 	depends on IP_NF_CONNTRACK!=y || NETFILTER_NETLINK!=m
+	depends on IP_NF_NAT=n || IP_NF_NAT
 	help
 	  This option enables support for a netlink-based userspace interface