Flight mode does not work properly on MTK devices when WiDi is on

Flight mode does not work properly on MTK devices (i.e. frieza) when WiDi is on: for instance, if we set flight mode and reboot, wifi will activate.

This happens because MTK devices do not use the standard kernel rfkill interface for setting flight mode. Instead, we use libhybris inside of urfkill to achieve this. aethercast does not take this into account and loads p2p firmware always, which produces wifi activation.

The solution for this would be to track flight mode status using urfkill DBus interface instead of rfkill.