Clean up keymint ProtectedData documentation am: 1d389acec8 am: 19eff513d4 am: 76626c0bda

Original change: https://android-review.googlesource.com/c/platform/hardware/interfaces/+/2075940

Change-Id: I299cdff5e29a57953274880d14d9ab87630a93e9
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>