Add a new property to ubus_subscriber called new_obj_cb. It gets called
everytime a new object appears on the bus. If the callback returns true,
libubus will automatically subscribe to the notifications.
Signed-off-by: John Crispin <john@phrozen.org>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
rename the ADD_WATCH/REMOVE_WATCH messages to SUBSCRIBE/UNSUBSCRIBE and change
the message format and libubus API in preparation for adding object notifications
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
