netfilter: fix NAT packaging with kernels 5.2+

It's related to the upstream kernel commit adf82accc5f5 ("netfilter:
x_tables: merge ip and ipv6 masquerade modules").

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>

include/netfilter.mk

@@ -202,7 +202,8 @@ $(eval $(if $(NF_KMOD),$(call nf_add,IPT_NAT6,CONFIG_IP6_NF_TARGET_NPT, $(P_V6)i
 $(eval $(if $(NF_KMOD),,$(call nf_add,IPT_NAT,CONFIG_NF_NAT, ipt_SNAT ipt_DNAT)))
 $(eval $(if $(NF_KMOD),,$(call nf_add,IPT_NAT6,CONFIG_IP6_NF_TARGET_NPT, ip6t_DNPT ip6t_SNPT)))
 
-$(eval $(call nf_add,IPT_NAT,CONFIG_IP_NF_TARGET_MASQUERADE, $(P_V4)ipt_MASQUERADE))
+$(eval $(call nf_add,IPT_NAT,CONFIG_IP_NF_TARGET_MASQUERADE, $(P_V4)ipt_MASQUERADE, lt 5.2))
+$(eval $(call nf_add,IPT_NAT,CONFIG_IP_NF_TARGET_MASQUERADE, $(P_XT)xt_MASQUERADE, ge 5.2))
 $(eval $(call nf_add,IPT_NAT,CONFIG_IP_NF_TARGET_REDIRECT, $(P_XT)xt_REDIRECT))