Merge "Document changes and clean up spec" am: 4ad2bb150e

Original change: https://android-review.googlesource.com/c/platform/hardware/interfaces/+/2308373

Change-Id: I9be585e03fdecfbd2471eff53561586923eda702
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>