Clarify the Weaver documentation am: a4742a0291 am: cf07ed821d

Original change: https://android-review.googlesource.com/c/platform/hardware/interfaces/+/2665198

Change-Id: I437cdabf4c8e014c27f41dc66500aa10a4508a2f
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>