AudioService: fix SCO audio resume after call

In AudioDeviceBroker.setCommunicationRouteForClient(),
if the requested device is SCO audio, start BT SCO audio
not only when SCO was not requested before but also if SCO audio
is not active.

Bug: 206739623
Test: repro steps in bug.
Test: atest AudioCommunicationDeviceTest
Change-Id: I36bd1f32811e0cd4db4ffc54a5fb189f0352cfe8