Optionally include the Secretkeeper TA am: 16ecbd275e

Original change: https://android-review.googlesource.com/c/trusty/device/arm/generic-arm64/+/2824499

Change-Id: Ifd21d2bdb7e563c419743be2ac67fa9e1d39e99e
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>