g2: update default wallpaper & screen brightness

* lower initial startup brightness
* fix usb tethering (thanks to arcardinal)

Signed-off-by: houst0nn <houstonn@gmail.com>
g2: add cmhw class for tap-to-wake

Signed-off-by: houst0nn <houstonn@gmail.com>
g2: battery leds

Signed-off-by: houst0nn <houstonn@gmail.com>