Fix race condition with SIM bouncer on start

The user could end up with a blank screen or a strange
looking lockscreeen.

The SIM bouncer may decide to show in two bad conditions:
1. The bouncer hasn't been bound yet - So return false
2. The device is entering doze but hasn't quite made it -
   so don't show it.

Test: atest StatusBarKeyguardViewManagerTest
Fixes: 351426938
Flag: com.android.systemui.sim_pin_race_condition_on_restart
Change-Id: I5f69563ee94aea092c2f179e66a5c51c67886fda