audio: add definition for new audio loopback input device

Bug: 15437484
Change-Id: I62da0596d405c3bb5e00b461f7d4fd11627ed391
diff --git a/include/system/audio.h b/include/system/audio.h
index c7cd109..8530efa 100644
--- a/include/system/audio.h
+++ b/include/system/audio.h
@@ -499,6 +499,7 @@
     /* S/PDIF in */
     AUDIO_DEVICE_IN_SPDIF                 = AUDIO_DEVICE_BIT_IN | 0x10000,
     AUDIO_DEVICE_IN_BLUETOOTH_A2DP        = AUDIO_DEVICE_BIT_IN | 0x20000,
+    AUDIO_DEVICE_IN_LOOPBACK              = AUDIO_DEVICE_BIT_IN | 0x40000,
     AUDIO_DEVICE_IN_DEFAULT               = AUDIO_DEVICE_BIT_IN | AUDIO_DEVICE_BIT_DEFAULT,
 
     AUDIO_DEVICE_IN_ALL     = (AUDIO_DEVICE_IN_COMMUNICATION |
@@ -519,6 +520,7 @@
                                AUDIO_DEVICE_IN_LINE |
                                AUDIO_DEVICE_IN_SPDIF |
                                AUDIO_DEVICE_IN_BLUETOOTH_A2DP |
+                               AUDIO_DEVICE_IN_LOOPBACK |
                                AUDIO_DEVICE_IN_DEFAULT),
     AUDIO_DEVICE_IN_ALL_SCO = AUDIO_DEVICE_IN_BLUETOOTH_SCO_HEADSET,
     AUDIO_DEVICE_IN_ALL_USB  = (AUDIO_DEVICE_IN_USB_ACCESSORY |