[FFmpeg-cvslog] mmst: fix reading uninitialized data for ping packets.

[Francesco Cosoleto]

2011/2/15 Ronald S. Bultje <git at videolan.org>:
> ffmpeg | branch: master | Ronald S. Bultje <rsbultje at gmail.com> | Mon Feb 14 09:55:14 2011 -0500| [e84314515ac39543641cd148a33b155218df6a74] | committer: Michael Niedermayer
>
> mmst: fix reading uninitialized data for ping packets.
>
> Fixes errors after a few minutes (first ping) when playing back
> mmst://wm.bbc.co.uk/wms/bbc7coyopa/bbc7_-_friday_0430.wma

It fixes a more common bug than what the commit message says.

Francesco