(filter, plugins) rename, avoid name collisions

src/etc/inc/plugins.inc.d/ifgroups.inc → src/etc/inc/plugins.inc.d/plugin_ifgroups.inc

@@ -26,7 +26,7 @@
     POSSIBILITY OF SUCH DAMAGE.
 */
 
-function ifgroups_interface()
+function plugin_ifgroups_interface()
 {
     global $config;
     $interfaces = array();

src/etc/inc/plugins.inc.d/ipsec.inc → src/etc/inc/plugins.inc.d/plugin_ipsec.inc

@@ -26,7 +26,7 @@
     POSSIBILITY OF SUCH DAMAGE.
 */
 
-function ipsec_interface()
+function plugin_ipsec_interface()
 {
     global $config;
     $interfaces = array();

src/etc/inc/plugins.inc.d/openvpn.inc → src/etc/inc/plugins.inc.d/plugin_openvpn.inc

@@ -26,7 +26,7 @@
 */
 
 
-function openvpn_interface()
+function plugin_openvpn_interface()
 {
     global $config;
     $interfaces = array();