dvbsubdec: Fix 0xf0 end detection

Based on a change by JULIAN GARDNER
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/dvbsubdec.c

@@ -798,7 +798,7 @@ static void dvbsub_parse_pixel_data_block(AVCodecContext *avctx, DVBSubObjectDis
     y_pos += top_bottom;
 
     while (buf < buf_end) {
-        if (x_pos >= region->width || y_pos >= region->height) {
+        if ((*buf!=0xf0 && x_pos >= region->width) || y_pos >= region->height) {
             av_log(avctx, AV_LOG_ERROR, "Invalid object location! %d-%d %d-%d %02x\n", x_pos, region->width, y_pos, region->height, *buf);
             return;
         }