Audio: add system usage to audio policy engine schemas am: acd4a677f0

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

Change-Id: I300d132d79ace1fe572ca47a5cb4c17b947e1330
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>