Increase TS packet size detection buffer.

Fixes warning message with ticket #68.

libavformat/mpegts.c

@@ -1450,7 +1450,7 @@ static int mpegts_read_header(AVFormatContext *s,
 {
     MpegTSContext *ts = s->priv_data;
     AVIOContext *pb = s->pb;
-    uint8_t buf[5*1024];
+    uint8_t buf[8*1024];
     int len;
     int64_t pos;