hal: add support for SPDIF and HDMI input for qcs405

Add support for SPDIF/HDMI/HDMI-ARC backend.

Change-Id: I24f307074f3ceed4d4f484e4482458084063da19
diff --git a/hal/msm8974/platform.h b/hal/msm8974/platform.h
index e0aa58d..01f1516 100644
--- a/hal/msm8974/platform.h
+++ b/hal/msm8974/platform.h
@@ -174,7 +174,9 @@
     SND_DEVICE_IN_HEADSET_MIC_FLUENCE,
     SND_DEVICE_IN_VOICE_SPEAKER_MIC,
     SND_DEVICE_IN_VOICE_HEADSET_MIC,
+    SND_DEVICE_IN_SPDIF,
     SND_DEVICE_IN_HDMI_MIC,
+    SND_DEVICE_IN_HDMI_ARC,
     SND_DEVICE_IN_BT_SCO_MIC,
     SND_DEVICE_IN_BT_SCO_MIC_NREC,
     SND_DEVICE_IN_BT_SCO_MIC_WB,
@@ -266,7 +268,9 @@
     DEFAULT_CODEC_TX_BACKEND = SLIMBUS_0_TX,
     USB_AUDIO_TX_BACKEND,
     BT_SCO_TX_BACKEND,
+    SPDIF_TX_BACKEND,
     HDMI_TX_BACKEND,
+    HDMI_ARC_TX_BACKEND,
     MAX_CODEC_BACKENDS
 };