policy_hal: Initial change for the new libaudiopolicymanager

- Upgrade policy_hal to use new AudioPolicyManager
  introduced by Google. The legacy AudioPolicyManagerBase
  class is replaced by AudioPolicyManager.
- Customized AudioPolicyManager needs to implement everything
  from /frameworks/av/service/audiopolicy/AudioPolicyManager
  and add extended changes on top of it
- This change implements stock AOSP AudioPolicyManager with no
  Additional changes.

Change-Id: I56f7c575e60c51876fc5eda59b2eaa29d4e77639