qpnp-vibrator: just return the voltage, not all the pretty stuff

* makes handling it userspace much easier

Change-Id: I6173577a70c2bb89ab8ee4d5079be6457310a00c
hall_sensor: add a uevent switch for the cover

* We'll use this for the custom DotView case app
* Also make sure to set the initial value after registering the switch

Change-Id: Ib6668f6628b82949a57a25487bfcf261d35f5d07