msm7x30: Add & enable DeviceSettings

Device specific settings extension
For now it supports button/keyboard backlight adjustment

Signed-off-by: Michael Bestas <mikeioannina@gmail.com>

Change-Id: Ibcb311e0f170289fe0102bf75be76909faadb919
DeviceSettings: Add DisplayHomeAsUp feature.

Enabled back feature by pressing the app icon at the top left corner.

Signed-off-by: Michael Bestas <mikeioannina@gmail.com>

Change-Id: Ia796fba852969788e9f0ca12d6b61785f09d7c70