smdk4412: advanced settings: add spen support back

Change-Id: Ia7243737261bf63e406cd550d417f80b0f9a92cf

Conflicts:
	DeviceSettings/res/values/config.xml
	DeviceSettings/res/values/strings.xml
	DeviceSettings/res/xml/screen_preferences.xml
	DeviceSettings/src/com/cyanogenmod/settings/device/DeviceSettings.java
	DeviceSettings/src/com/cyanogenmod/settings/device/ScreenFragmentActivity.java
	DeviceSettings/src/com/cyanogenmod/settings/device/Startup.java