pictordec: stop using deprecated avcodec_set_dimensions

libavcodec/pictordec.c

@@ -141,9 +141,9 @@ static int decode_frame(AVCodecContext *avctx,
     avctx->pix_fmt = AV_PIX_FMT_PAL8;
 
     if (s->width != avctx->width && s->height != avctx->height) {
-        if (av_image_check_size(s->width, s->height, 0, avctx) < 0)
-            return -1;
-        avcodec_set_dimensions(avctx, s->width, s->height);
+        ret = ff_set_dimensions(avctx, s->width, s->height);
+        if (ret < 0)
+            return ret;
     }
 
     if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) {