audio: 24 bit audio output profiles

1) Use 24 bit COPP as default,
2) Select 24 bit as backend bit width if possible
3) Allow output streams in audio HAL to be configured by
   AF with format(s) listed in the policy_config xml

Test: low-latency, deep buffer, offload, ULL, voice call,
       USB playback, USB+Speaker combo playback
Bug: 62918461

Change-Id: I62575c1d7072abe782be58baad4bad30aa5fd0be