Fix segmentation fault with aspect ratio menu entry.

Without video stream guiInfo.sh_video isn't set.

Reported by Hans-Dieter Kosch, hdkosch kabelbw de.


git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@36393 b3059339-0415-0410-9bf9-f77b7e298cf2