netfilter: {ipt,ebt}_ULOG: rise warning on deprecation

This target has been superseded by NFLOG. Spot a warning
so we prepare removal in a couple of years.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Gao feng <gaofeng@cn.fujitsu.com>

include/net/netns/x_tables.h

@@ -15,5 +15,11 @@ struct netns_xt {
 	struct ebt_table *frame_filter;
 	struct ebt_table *frame_nat;
 #endif
+#if IS_ENABLED(CONFIG_IP_NF_TARGET_ULOG)
+	bool ulog_warn_deprecated;
+#endif
+#if IS_ENABLED(CONFIG_BRIDGE_EBT_ULOG)
+	bool ebt_ulog_warn_deprecated;
+#endif
 };
 #endif