mpegtsenc: allocate correct size for PID table

Originally committed as revision 23951 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/mpegtsenc.c

@@ -412,7 +412,7 @@ static int mpegts_write_header(AVFormatContext *s)
     ts->sdt.write_packet = section_write_packet;
     ts->sdt.opaque = s;
 
-    pids = av_malloc(s->nb_streams);
+    pids = av_malloc(s->nb_streams * sizeof(*pids));
     if (!pids)
         return AVERROR(ENOMEM);