Remove redundant initialization of the palette, it is part of the context

and that one is always 0-initialized already.

Originally committed as revision 21398 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/vb.c

@@ -272,8 +272,6 @@ static av_cold int decode_init(AVCodecContext *avctx)
     c->frame      = av_mallocz(avctx->width * avctx->height);
     c->prev_frame = av_mallocz(avctx->width * avctx->height);
 
-    memset(c->pal, 0, sizeof(c->pal));
-
     return 0;
 }