Disable slider shortcuts with custom lockscreen

These are not available with the custom lockscreen.

Change-Id: Ib67b97b597da0cf06d9d36b4fe7b40b55d0e2425
Signed-off-by: Roman Birg <roman@cyngn.com>

Conflicts:
	src/com/android/settings/cyanogenmod/LockscreenInterface.java