libweston: Init the output power state to normal
For shells like kiosk-shell which do not have some kind of a client to commit their surface, initialize the power output state to normal to trigger a repaint when the shell starts up. This would fix up kiosk-shell not displaying the background when starting up.
Fixes: 342243e8
Signed-off-by: Marius Vlad marius.vlad@collabora.com