Fix for Pixel Udfps to release peak refresh rate

The under-display fingerprint sensor's high-brightness mode (HBM)
implementation for Pixels was not calling onHbmDisabled under some
conditions, preventing DisplayModeDirector's HbmObserver from learning
that HBM has ended and a higher refresh rate is no longer required.

Test: `adb shell dumpsys display` should now show mLocalHbmEnabled
as disabled for Display 0 after successful fingerprint unlocks.

You can use `adb shell cmd display dmd-logging-enable` for logging
of DisplayModeDirector events if further troubleshooting is needed.

Issue: calyxos#1176
Change-Id: Ife66b62b2122a5958fcfc22e169df4b32841c69f