PM: devfreq: Use high priority workqueue

It does not make sense to run kgsl on high and devfreq on regular
priority.

Signed-off-by: flar2 <asegaert@gmail.com>
Disable magnetic cover event

Signed-off-by: flar2 <asegaert@gmail.com>
Adjust some voltages

Signed-off-by: flar2 <asegaert@gmail.com>