btaa: initialize BTAA service and JNI interface upon adapter creation

Initialize BTAA service and its JNI interface on adapter creation.

Tag: #feature
Bug: 172501038
Test: atest BluetoothInstrumentationTests:com.android.bluetooth.\
btservice.activityattribution

Change-Id: Iec50f67bddf9082a14abc3dcd92d1efedde4087b