hal: add rear seat playback support for automotive

Add rear seat playback support for multi-zone
audio support on automotive platform.

Change-Id: Ia3d4c4a4f78950e99a8d4955e910cc8902b6bb17
diff --git a/hal/audio_hw.c b/hal/audio_hw.c
index e541281..5840686 100644
--- a/hal/audio_hw.c
+++ b/hal/audio_hw.c
@@ -406,6 +406,7 @@
     [USECASE_AUDIO_PLAYBACK_SYS_NOTIFICATION] = "sys-notification-playback",
     [USECASE_AUDIO_PLAYBACK_NAV_GUIDANCE] = "nav-guidance-playback",
     [USECASE_AUDIO_PLAYBACK_PHONE] = "phone-playback",
+    [USECASE_AUDIO_PLAYBACK_REAR_SEAT] = "rear-seat-playback",
     [USECASE_AUDIO_FM_TUNER_EXT] = "fm-tuner-ext",
 };
 
@@ -5140,8 +5141,7 @@
             mixer_ctl_set_array(ctl, volume, sizeof(volume)/sizeof(volume[0]));
             return 0;
         } else if ((out->devices & AUDIO_DEVICE_OUT_BUS) &&
-                (audio_extn_auto_hal_get_snd_device_for_car_audio_stream(out) ==
-                    SND_DEVICE_OUT_BUS_MEDIA)) {
+                (out->car_audio_stream == CAR_AUDIO_STREAM_MEDIA)) {
             ALOGD("%s: Overriding offload set volume for media bus stream", __func__);
             struct listnode *node = NULL;
             list_for_each(node, &adev->active_outputs_list) {