mkv: mark corrupted packets and return them

Do return error if memory allocation or I/O fails.

libavformat/matroskadec.c

@@ -2069,6 +2069,11 @@ static int matroska_read_packet(AVFormatContext *s, AVPacket *pkt)
         ret = matroska_parse_cluster(matroska);
     }
 
+    if (ret == AVERROR_INVALIDDATA) {
+        pkt->flags |= AV_PKT_FLAG_CORRUPT;
+        return 0;
+    }
+
     return ret;
 }