fix for OpenWrt Ticket #18018 in BB 14.07 release.
Without fix the application writes a config without event interface
which causes ddns-scripts to NEVER start.
Signed-off-by: Christian Schoenebeck <christian.schoenebeck@gmail.com>
s:option(Flag, "enabled", translate("Enable"))
+interface = s:option(ListValue, "interface", translate("Event interface"), translate("Network on which the ddns-updater scripts will be started"))
+luci.tools.webadmin.cbi_add_networks(interface)
+interface.default = "wan"
+
svc = s:option(ListValue, "service_name", translate("Service"))
svc.rmempty = false
svc.default = "dyndns.org"