Merge "Adding Tethering proto" am: 075dd6f8ff am: cd4493204a

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/2024488

Change-Id: Ibd55e5c8fae5e631776f75cc5f699b88b792ae9c
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>