AudioService: fix isInCommunication()

Consider we are in call also when audio mode is MODE_IN_CALL.
This removes race conditions occuring when there is a delay between
audio mode being set to MODE_IN_CALL and the actual call state updated
in TelecomManager.

Bug: 70690373
Test: test DTMF level at various call volume on earpiece, speaker, USB
headset

Change-Id: I5e905a36e825211b6d780a285fc7b47cea3edf2b