Enable support for main type cap aware demux management

Adding 3 ITuner.aidl APIs:
 - int[] getDemuxIds();
 - IDemux openDemuxById(in int demuxId);
 - DemuxInfo getDemuxInfo(in int demuxId);

And adding DemuxInfo.aidl.

Bug: 239211919
Bug: 239227510
Test: atest VtsHalTvTunerTargetTest

Change-Id: Icd34cc974a6f6fa167d90b69b3ff0a119bf50ae8