policy_hal: hal: add support to enable Direct PCM

- Add support for direct pcm output

- Add support for direct pcm in hal
  if output flag is direct_pcm choose compress offload path

- Add support for direct pcm in custom audio policy manager
  force add direct flag when we detect pcm track in music and
  game use case

Change-Id: Ie69c988ef9cd0477efa77611ceddccdd6b17a163
diff --git a/hal/msm8916/platform.h b/hal/msm8916/platform.h
index 5d0ad2d..7a25b70 100644
--- a/hal/msm8916/platform.h
+++ b/hal/msm8916/platform.h
@@ -248,6 +248,8 @@
 #define SPKR_PROT_CALIB_RX_PCM_DEVICE 5
 #define SPKR_PROT_CALIB_TX_PCM_DEVICE 26
 #define PLAYBACK_OFFLOAD_DEVICE 9
+#define PLAYBACK_OFFLOAD_DEVICE2 24
+
 
 #define COMPRESS_VOIP_CALL_PCM_DEVICE 3