Add support for USB headset device

Add missing rules for USB headset devices in routing, volume and effects
management.

Test: playback and catpure regression tests.
Change-Id: I42cd157f483deba2371a05d332cd11dceb2b2fa3
diff --git a/media/libeffects/preprocessing/PreProcessing.cpp b/media/libeffects/preprocessing/PreProcessing.cpp
index ccfd29c..f2844ed 100644
--- a/media/libeffects/preprocessing/PreProcessing.cpp
+++ b/media/libeffects/preprocessing/PreProcessing.cpp
@@ -531,6 +531,7 @@
         break;
     case AUDIO_DEVICE_OUT_WIRED_HEADSET:
     case AUDIO_DEVICE_OUT_WIRED_HEADPHONE:
+    case AUDIO_DEVICE_OUT_USB_HEADSET:
     default:
         break;
     }