Simplify dependencies in dspr2 related codes

The common_dspr2.h should be independent of codec-specific data
structures.

Change-Id: I34ee1f9552c2d2d205fd7f1813cdf312c7ff5d2b

vp9/common/mips/dspr2/vp9_common_dspr2.h

@@ -15,7 +15,6 @@
 
 #include "./vpx_config.h"
 #include "vpx/vpx_integer.h"
-#include "vp9/common/vp9_common.h"
 
 #ifdef __cplusplus
 extern "C" {