Don't overtrigger face auth (ie: goingToSleep, lockdown)

* Keyguard will no longer start to face authenticate when a user
has pressed the power button from bouncer.
* Also, don't run face scanning if bypass isn't enabled and
the device is in lockdown. The non-bypass flow doesn't trigger
the bouncer after face scan.

Test: Verified Face authentication no longer auths when device is going
to sleep.
Test: Verified rear fps still works after power off device.
Test: Verified face auth doesn't run when bypass isn't enabled, in
lockdown, press power button to turn on the display - face auth doesn't
run
Fixes: 196013443

Change-Id: I40cd1d7b9bdfd30ef995ffad02b14a351a413dd9