audio : Mute FM when ringtone is played from settings

- FM audio on speaker is getting mixed up with ringtone
  when it is played from settings.
- Fix is to mute FM audio by enabling the combo device for
  sonification strategy even if the speaker is force used
  for media.
  CRs-Fixed: 574271

Change-Id: Ic595f326d7409b4cb557f5f1edf8f3bf58ce60c8