Settings: 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>
Settings: read keyguard package name from overlays

Change-Id: Ief4750c91aa22c2033d31aacfea4cfbe245d61a8
Signed-off-by: Roman Birg <roman@cyngn.com>
Settings: check if NfcAdapter is null

Change-Id: Ib71762b5a5326ade5cab3bebb9b880bdeb7da178