A2DP offload: modify the A2DP offload SCMS-T_Enable with SCMS-T header

Follow the Android HCI requirement for the 'Start A2DP Offload' cmd, it
should bring the SCMS-T header in the 'SCMS-T Enable' field as SCMS-T is
enabled. Get the SCMS-T active status of the peer devices as building
the offload start req cmd, and fill the SCMS-T header based the active
status.

Bug: 170785181
Tag: #feature
Test: connect with Sony WH-1000XM4, check the SCMS-T_Enable correctness
Test: atest --test-mapping system/bt
Change-Id: I6003b50a09f010942b37436497b06e06180b2069