Removed unused diff buffer

Change-Id: I9211358cca89b1c4f84b53a202a63ecf9e79ae4c

vp8/common/blockd.h

diff --git a/vp8/common/blockd.h b/vp8/common/blockd.h
index 91e90e2..586fa0a 100644
--- a/vp8/common/blockd.h
+++ b/vp8/common/blockd.h
@@ -187,7 +187,6 @@
     short *qcoeff;
     short *dqcoeff;
     unsigned char  *predictor;
-    short *diff;
     short *dequant;
 
     /* 16 Y blocks, 4 U blocks, 4 V blocks each with 16 entries */
@@ -206,7 +205,6 @@
 
 typedef struct MacroBlockD
 {
-    DECLARE_ALIGNED(16, short, diff[400]);      /* from idct diff */
     DECLARE_ALIGNED(16, unsigned char,  predictor[384]);
     DECLARE_ALIGNED(16, short, qcoeff[400]);
     DECLARE_ALIGNED(16, short, dqcoeff[400]);

vp8/common/mbpitch.c

diff --git a/vp8/common/mbpitch.c b/vp8/common/mbpitch.c
index 11fa3ff..f8971d7 100644
--- a/vp8/common/mbpitch.c
+++ b/vp8/common/mbpitch.c
@@ -87,7 +87,6 @@
     {
         for (c = 0; c < 4; c++)
         {
-            x->block[r*4+c].diff      = &x->diff[r * 4 * 16 + c * 4];
             x->block[r*4+c].predictor = x->predictor + r * 4 * 16 + c * 4;
         }
     }
@@ -96,7 +95,6 @@
     {
         for (c = 0; c < 2; c++)
         {
-            x->block[16+r*2+c].diff      = &x->diff[256 + r * 4 * 8 + c * 4];
             x->block[16+r*2+c].predictor = x->predictor + 256 + r * 4 * 8 + c * 4;
 
         }
@@ -106,14 +104,11 @@
     {
         for (c = 0; c < 2; c++)
         {
-            x->block[20+r*2+c].diff      = &x->diff[320+ r * 4 * 8 + c * 4];
             x->block[20+r*2+c].predictor = x->predictor + 320 + r * 4 * 8 + c * 4;
 
         }
     }
 
-    x->block[24].diff = &x->diff[384];
-
     for (r = 0; r < 25; r++)
     {
         x->block[r].qcoeff  = x->qcoeff  + r * 16;