policy_hal: add support for fm device loopback

Use device connection event against AUDIO_DEVICE_OUT_FM
to configure FM device loopback.
Update primary output to get routing and volume events.

Change-Id: I5ddce36581568d377a08ea5afe470bdff4349ec7
diff --git a/policy_hal/Android.mk b/policy_hal/Android.mk
index 52ed11d..70814d8 100644
--- a/policy_hal/Android.mk
+++ b/policy_hal/Android.mk
@@ -59,6 +59,10 @@
     LOCAL_CFLAGS += -DAUDIO_EXTN_AFE_PROXY_ENABLED
 endif
 
+ifeq ($(strip $(AUDIO_FEATURE_ENABLED_FM_POWER_OPT)),true)
+LOCAL_CFLAGS += -DFM_POWER_OPT
+endif
+
 LOCAL_MODULE := libaudiopolicymanager
 
 include $(BUILD_SHARED_LIBRARY)