[flexi] 1f device entry icon background alpha when KS.UNDEFINED

We only want to hide the device entry icon when
the Scene is Lockscreen (betwen some KTF transitions).

Otherwise, the device entry icon and its background should
be 1f, including when the KeyguardState is UNDEFINED (which means
its on a non-lockscreen scene).

Test: manually swipe down and up on the lockscreen,
see device entry icon with background shows
Fixes: 379845752
Flag: EXEMPT bugfix

Change-Id: I16395a61b12c66b43757c709ec0bf43f580e617d