Merge "keymint: document deprecation of UNLOCKED_DEVICE_REQUIRED enforcement" into main am: 8c7558625f

Original change: https://android-review.googlesource.com/c/platform/hardware/interfaces/+/2966026

Change-Id: I4a1416d471eb98a0b826bcad02384e583378d075
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>