audio: Fix to return proper channel index masks supported for USB

Channel Index mask was coming zero when queried through
getChannelIndexMask API in Tunnel Mode for USB CTSVerifer
since supported channel mask array was not filled
ChannelIndexMask details.

Add changes to fill supported channel mask array with both channel
 maks and ChannelIndexMask in accordance with Non Tunnel Mode
so that USB CTSVerifer gets the proper channel and ChanneIndexmask
count when queried through corresponding API's.

CRs-Fixed:2330574

Change-Id: I9a07343536df6d8c676c1b9bf8c7a5b320ad8ad2