AudioDeviceBroker: fix communication client death

Make sure that SCO audio is deactivated when a communication
route client dies. Previous implementation was just removing the client
from the list and updating the current route but wihout requesting the
BT Helper to stop SCO.

Bug: 243096994
Test: repro steps i nthe bug
Change-Id: I09d0e4965933d70e815abe4a24fd3060f0a11564