audio: Add dedicated streams for VoIP call

Add dedicated streams for VoIP usecase. This includes adding
a new direct output and input types that use audio playback
and record paths respectively. It falls back to compress VoIP
wherever this feature is not applicable.

Change-Id: I9b7654819b9d8deb00f8888fbfc31f0fbbae5266
diff --git a/hal/msm8916/platform.h b/hal/msm8916/platform.h
index f8c7280..17bd8f2 100644
--- a/hal/msm8916/platform.h
+++ b/hal/msm8916/platform.h
@@ -330,6 +330,8 @@
 #define PLAYBACK_OFFLOAD_DEVICE 9
 #define PLAYBACK_OFFLOAD_DEVICE2 24
 #define COMPRESS_VOIP_CALL_PCM_DEVICE 3
+#define AUDIO_PLAYBACK_VOIP_PCM_DEVICE 16
+#define AUDIO_RECORD_VOIP_PCM_DEVICE 16
 
 /* Define macro for Internal FM volume mixer */
 #ifdef PLATFORM_MSMFALCON