Audio: add system usage to audio policy engine schemas am: acd4a677 am: 2b10decf

Original change: https://android-review.googlesource.com/c/platform/hardware/interfaces/+/2689186



Change-Id: I376b0c6278a1551cb1e2d753d40e79b1b1c1d2ac
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>