fix end of buffer check, fix hang_read_header.h264.ts

Originally committed as revision 18454 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/mpegts.c

@@ -555,7 +555,7 @@ static void pmt_cb(MpegTSFilter *filter, const uint8_t *section, int section_len
         if (desc_list_len < 0)
             break;
         desc_list_end = p + desc_list_len;
-        if (desc_list_end > p_end)
+        if (desc_list_end >= p_end)
             break;
         for(;;) {
             desc_tag = get8(&p, desc_list_end);