Log power & face auth wake reasons.

This replaces the fixed UNKNOWN placeholder value that was put in place after the logs were approved but the signal was not yet available from SysUI.

Bug: 242628816
Fix: 273493643
Test: statsd_testdrive 88 87 89 (manual, unlock via keyguard and verify atom data)
Test: atest BiometricFrameworkStatsLoggerTest
Change-Id: Ib6cb069a7a952ce46cb937770842315a69b6b3f0