avcodec/vp56: Add () to protect TRANSPOSE()s arguments

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/vp56.c

@@ -701,7 +701,7 @@ av_cold int ff_vp56_init_context(AVCodecContext *avctx, VP56Context *s,
     ff_vp3dsp_init(&s->vp3dsp, avctx->flags);
     ff_vp56dsp_init(&s->vp56dsp, avctx->codec->id);
     for (i = 0; i < 64; i++) {
-#define TRANSPOSE(x) (x >> 3) | ((x & 7) << 3)
+#define TRANSPOSE(x) (((x) >> 3) | (((x) & 7) << 3))
         s->idct_scantable[i] = TRANSPOSE(ff_zigzag_direct[i]);
 #undef TRANSPOSE
     }