coova-chilli: add interface_trigger "wan"

This intends to replace the hotplug script. It still hardcodes "wan"
interface name (as several other packages do) for lack of a deterministic
way to detect the actual wan iface before it is brought up, but at least
it is fully integrated with procd and will not start a disabled service.

The interface trigger forcefully restarts chilli as a simple reload may
not be sufficient to recover from wan changes.

Signed-off-by: Thibaut VARÈNE <hacks@slashdirt.org>

net/coova-chilli/files/chilli.init

@@ -6,6 +6,7 @@ USE_PROCD=1
 
 service_triggers() {
 	procd_add_reload_trigger "chilli"
+	procd_add_interface_trigger "interface.*.up" "wan" /etc/init.d/chilli restart
 }
 
 config_cb() {