Always use an address for remote submix

Usage of remote submix device for audio rerouting (e.g. wifi display)
 didn't mandate the use of addresses. Use "0" as the default address
 when none is specificed.
In logs, only use hex format for audio devices

Bug 16009464

Change-Id: Ibfb1ce6881eba8b7e34420293b8a7077a6e659e6