Clean up libaudioclient includes

Test: build
Change-Id: I1b2cd96e99564cd3944aa20a36207bd91287f7c8
diff --git a/media/libmediaplayerservice/MediaPlayerService.h b/media/libmediaplayerservice/MediaPlayerService.h
index 49688ce..2562b8f 100644
--- a/media/libmediaplayerservice/MediaPlayerService.h
+++ b/media/libmediaplayerservice/MediaPlayerService.h
@@ -26,10 +26,12 @@
 #include <utils/String8.h>
 #include <utils/Vector.h>
 
+#include <media/AudioSystem.h>
 #include <media/MediaPlayerInterface.h>
 #include <media/Metadata.h>
 #include <media/stagefright/foundation/ABase.h>
 
+
 #include <system/audio.h>
 
 namespace android {