hal: Backend port specific channel mapping for afe-loopback

- Add support for Backend port specific channel map for
  afe-loopback usecase.

Change-Id: I7a246a97d5ca38e084e4675563bb283d839ac0fe
diff --git a/hal/msm8916/platform.c b/hal/msm8916/platform.c
index 5233e5c..baf67d7 100644
--- a/hal/msm8916/platform.c
+++ b/hal/msm8916/platform.c
@@ -4342,8 +4342,8 @@
     } else if (devices & AUDIO_DEVICE_OUT_ANLG_DOCK_HEADSET ||
                devices & AUDIO_DEVICE_OUT_DGTL_DOCK_HEADSET) {
         ALOGD("%s: setting USB hadset channel capability(2) for Proxy", __func__);
-        audio_extn_set_afe_proxy_channel_mixer(adev, 2);
         snd_device = SND_DEVICE_OUT_USB_HEADSET;
+        audio_extn_set_afe_proxy_channel_mixer(adev, 2, snd_device);
     } else if (devices &
                 (AUDIO_DEVICE_OUT_USB_DEVICE |
                  AUDIO_DEVICE_OUT_USB_HEADSET)) {
@@ -4363,8 +4363,8 @@
     } else if (devices & AUDIO_DEVICE_OUT_PROXY) {
         channel_count = audio_extn_get_afe_proxy_channel_count();
         ALOGD("%s: setting sink capability(%d) for Proxy", __func__, channel_count);
-        audio_extn_set_afe_proxy_channel_mixer(adev, channel_count);
         snd_device = SND_DEVICE_OUT_AFE_PROXY;
+        audio_extn_set_afe_proxy_channel_mixer(adev, channel_count, snd_device);
     } else {
         ALOGE("%s: Unknown device(s) %#x", __func__, devices);
     }