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

Change-Id: Iba482d8b72bfa2675877d833d7abcb93d4cf4907
diff --git a/mm-audio/Android.mk b/mm-audio/Android.mk
index 5053e7d..3885afc 100644
--- a/mm-audio/Android.mk
+++ b/mm-audio/Android.mk
@@ -1 +1,3 @@
+ifeq ($(strip $(TARGET_USES_QCOM_MM_AUDIO)),true)
 include $(call all-subdir-makefiles)
+endif