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_policy.c b/modules/audio/audio_policy.c
index 4d5258d..8afef5f 100644
--- a/modules/audio/audio_policy.c
+++ b/modules/audio/audio_policy.c
@@ -23,7 +23,7 @@
 #include <string.h>
 
 #include <hardware/hardware.h>
-#include <hardware/audio.h>
+#include <system/audio.h>
 #include <hardware/audio_policy.h>
 #include <hardware/audio_policy_hal.h>