audio: Update default wrapper to support V7

During this conversion, the functionality of the V7 wrapper
hasn't been tested yet. This will be done in a separate CL
that will also include required updates to the VTS tests.

Since the changes were made to the code shared with pre-V7
versions, verified that V6 HAL didn't regress.

Bug: 142480271
Test: atest VtsHalAudioV6_0TargetTest
Test: m VtsHalAudioV7_0TargetTest
Change-Id: I0e42fe1279912ffa78ce40c69f6aa2054e84d385
Merged-In: I0e42fe1279912ffa78ce40c69f6aa2054e84d385