bitstream_debug: build related cleanup

Move experimental config from debug_util.c/h to aom_util.mk to avoid
empty object.

Change-Id: Id7978ed6a342262bddaa4df8b53115e750fa1c2c
diff --git a/aom_util/debug_util.c b/aom_util/debug_util.c
index ca666a1..0385df7 100644
--- a/aom_util/debug_util.c
+++ b/aom_util/debug_util.c
@@ -8,10 +8,10 @@
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
-#include "aom_util/debug_util.h"
 #include <assert.h>
 #include <stdio.h>
-#if CONFIG_BITSTREAM_DEBUG
+#include "aom_util/debug_util.h"
+
 #define QUEUE_MAX_SIZE 2000000
 static int result_queue[QUEUE_MAX_SIZE];
 static int prob_queue[QUEUE_MAX_SIZE];
@@ -27,11 +27,11 @@
 
 void bitstream_queue_set_frame_write(int frame_idx) { frame_idx_w = frame_idx; }
 
-int bitstream_queue_get_frame_write() { return frame_idx_w; }
+int bitstream_queue_get_frame_write(void) { return frame_idx_w; }
 
 void bitstream_queue_set_frame_read(int frame_idx) { frame_idx_r = frame_idx; }
 
-int bitstream_queue_get_frame_read() { return frame_idx_r; }
+int bitstream_queue_get_frame_read(void) { return frame_idx_r; }
 
 void bitstream_queue_set_skip_write(int skip) { skip_w = skip; }
 
@@ -68,4 +68,3 @@
     }
   }
 }
-#endif  // CONFIG_BITSTREAM_DEBUG