libvpx: Add VP9 decoder.

source/libvpx/vp9/decoder/x86/vp9_idct_mmx.h

+/*
+ *  Copyright (c) 2010 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.
+ */
+
+#ifndef VP9_DECODER_X86_VP9_IDCT_MMX_H_
+#define VP9_DECODER_X86_VP9_IDCT_MMX_H_
+
+
+void vp9_dequant_dc_idct_add_mmx(short *input, const short *dq,
+                                 unsigned char *pred, unsigned char *dest,
+                                 int pitch, int stride, int Dc);
+
+void vp9_dc_only_idct_add_mmx(short input_dc, const unsigned char *pred_ptr,
+                              unsigned char *dst_ptr, int pitch, int stride);
+
+void vp9_dequant_idct_add_mmx(short *input, const short *dq, unsigned char *pred,
+                              unsigned char *dest, int pitch, int stride);
+
+#endif /* VP9_DECODER_X86_VP9_IDCT_MMX_H_ */