audio_policy: Fix for mute count mismatch for sonification strategy

- Sometime ring tone is not heard while in MT call

- During call mode, primary output ringtone/alarm stream mute count
  is incremented on startOutput and decremented on stopoutput
  for all Output requests.
    This is resulting side effect if stop output for non-primary outputs
  called, when no active streams available on primary output(mute count
  will not decrement)

- Add requested output check on start & stop output before calling
  handleIncallSonification API

Change-Id: Id4f328e2f9fc6820cecfbd73df11c871f8587aad