Dynamic Audio Buffer (3/3)

Handle the dynamic audio buffer in the BT stack:
1. Send HCI VSC command to the controller.
2. Receive HCI VSC event from the controller.
3. Communicate with framework.

Bug: 163968696
Tag: #feature
Test: Run dynamic audio buffer test
Change-Id: I6a699c2c24b714ce76d1fad858574f2438b64262