audio: Add missing fields from APM XSD schema to structs

Since APM XML configuration is being replaced with data
provided by the HAL, add data fields used to be in the APM XSD
schema to HAL structures. Summary of changes:

- Audio*Flags enum types moved to HAL types because flags
  are specified for mixPorts in the APM config;
- AudioGainSys.useForVolume -> AudioGain;
- added AudioPort.flags because they are specified in the
  APM config for mixPorts; since AudioIoFlags is a union,
  it will be used for determining the mix port role;
- added AudioPortMixExt.max{Open|Active}Count;
- added AudioPortMixExt.recommendedMuteDurationMs;
- AudioPortConfigSys.flags -> AudioPortConfig
  this is for symmetry with AudioPort;
- added AudioPortDeviceExt which encapsulates device
  and encodedFormats information for device ports.

Bug: 198812639
Test: atest audiofoundation_parcelable_test
Change-Id: Id5fd537b11e43e85b3caa93b2cb3bc7f482a3199