add rule count stat

src/inc_internal/maat_ip_plugin.h

@@ -47,6 +47,8 @@ int ip_plugin_runtime_update(void *ip_plugin_runtime, void *ip_plugin_schema,
                              const char *table_name, const char *line, int valid_column);
 int ip_plugin_runtime_commit(void *ip_plugin_runtime, const char *table_name);
 
+long long ip_plugin_runtime_rule_count(void *ip_plugin_runtime);
+
 struct ex_data_runtime *ip_plugin_runtime_get_ex_data_rt(void *ip_plugin_runtime);
 
 int ip_plugin_runtime_get_ex_data(void *ip_plugin_runtime, const struct ip_addr *ip_addr,