gpio_input: adding back power button to input for later use

Adding back Power button handling to GPIO input driver and
m7 panel to let it work with screen/gyro wake options.
Adding KEY_POWER skip sync to the handling of that button
so it won't spoil the normal screen on process of the m7.
input/misc/panel: adding tap wake and gyro wake options

Implementations by @tbalden
- Additional vibrate extern for use within wake options.
- Adding Near only pocket detection
- Adding panel callback to let gyro know screen is on/off
mach-msm: adding user space voltage control and fastcharge options
leds pm8xxx-htc: adding Button light notif (blinking buttons)

Implementation by @tbalden
defconfig: teamseven config