Merge "Explain how to add service_contexts for stable-c mapper" into main am: 1b20111074

Original change: https://android-review.googlesource.com/c/platform/hardware/interfaces/+/3062802

Change-Id: Ica665bdb09e20c763078e17a6675e69ece9f830b
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>