hal: update audio feature flags

- update audio feature flags to use
  AUDIO_FEATURE_ENABLED_XXX instead of
  AUDIO_FEATURE_DISABLED_XXX.
- These feature flags are defined
  by target board config file

Conflicts:
	hal/Android.mk
	hal/audio_extn/audio_extn.h
	policy_hal/Android.mk
	post_proc/Android.mk

Conflicts:
	mm-audio/Android.mk
	policy_hal/Android.mk
	post_proc/Android.mk

Change-Id: Iba482d8b72bfa2675877d833d7abcb93d4cf4907