Make face auth ineligible when camera access is disabled

Test: Disable camera access in Settings, Open biometric prompt test app
and try to authenticate; Fingerprint authentication should work normally
Bug: 277854521
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:c35a712ab4308e0281c8b2a7adfae8de42d28a6a)
Merged-In: I19556fa7f861f2f7655e792b1da9d74d3cf2259e
Change-Id: I19556fa7f861f2f7655e792b1da9d74d3cf2259e