Add line about VENET zone

--- ./conf/fiaif.conf
+++ ./conf/fiaif.conf
@@ -38,6 +38,7 @@ ZONES="EXT"
 CONF_INT=zone.int
 CONF_EXT=zone.ext
 CONF_DMZ=zone.dmz
+CONF_VENET=zone.venet
 
 ## Use iptables-save and iptables restore to speed up 
 ## Startup scripts. You should leave this setting to 0.