libvpx: Pull from upstream

source/libvpx/vp8/common/arm/neon/vp8_subpixelvariance_neon.c

 /*
  *  Copyright (c) 2014 The WebM project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
 #include <arm_neon.h>
 #include "vpx_ports/mem.h"
 #include "vpx/vpx_integer.h"
 
-#ifdef _MSC_VER
-#define __builtin_prefetch(x)
-#endif
-
 static const uint16_t bilinear_taps_coeff[8][2] = {
     {128,   0},
     {112,  16},
     { 96,  32},
     { 80,  48},
     { 64,  64},
     { 48,  80},
     { 32,  96},
     { 16, 112}
 };
@@ skipping 990 matching lines @@
   } else {
     var_filter_block2d_bil_w8(src, fdata3, src_stride, kPixelStepOne,
                               kHeight8PlusOne, kWidth8,
                               bilinear_taps_coeff[xoffset]);
     var_filter_block2d_bil_w8(fdata3, temp2, kWidth8, kWidth8, kHeight8,
                               kWidth8, bilinear_taps_coeff[yoffset]);
   }
   return variance8x8_neon(temp2, kWidth8, dst, dst_stride, sse);
 }