[thread] Support non-BR mode am: 82988c3d98 am: 931e27df25

Original change: https://android-review.googlesource.com/c/platform/packages/modules/Connectivity/+/3532110

Change-Id: Ie40b15199010b35adc31c734a396a6e0b9b13382
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>