src: introduce struct xt_xlate_{mt,tg}_params

This structure is an extensible containers of parameters, so we don't
need to propagate interface updates in every extension file in case
we need to add new parameters in the future.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
diff --git a/extensions/libipt_LOG.c b/extensions/libipt_LOG.c
index f81eb8d..996dfb6 100644
--- a/extensions/libipt_LOG.c
+++ b/extensions/libipt_LOG.c
@@ -182,12 +182,12 @@
 	{"warn",	LOG_WARNING }
 };
 
-static int LOG_xlate(const void *ip, const struct xt_entry_target *target,
-		     struct xt_xlate *xl, int numeric)
+static int LOG_xlate(struct xt_xlate *xl,
+		     const struct xt_xlate_tg_params *params)
 {
-	unsigned int i = 0;
 	const struct ipt_log_info *loginfo =
-			(const struct ipt_log_info *)target->data;
+		(const struct ipt_log_info *)params->target->data;
+	unsigned int i = 0;
 
 	xt_xlate_add(xl, "log ");
 	if (strcmp(loginfo->prefix, "") != 0)