audio: move audio.h to system/core/include/system/audio.h

Change-Id: I523dfb361b1b3862cf8bc41c1691c607b2c815b0
Signed-off-by: Dima Zavin <dima@android.com>
diff --git a/modules/audio/audio_hw.c b/modules/audio/audio_hw.c
index bb6659d..b3ab1e2 100644
--- a/modules/audio/audio_hw.c
+++ b/modules/audio/audio_hw.c
@@ -25,7 +25,7 @@
 #include <cutils/log.h>
 
 #include <hardware/hardware.h>
-#include <hardware/audio.h>
+#include <system/audio.h>
 #include <hardware/audio_hal.h>
 
 struct stub_audio_device {