'Zoom to Layer' options have always the default values

You can see this issue when you configure a OpenLayers Map field in CCK.
Set the options of the Zoom to Layer fieldset to some values and save.
Then open the field settings page again and the default values will be there. (in the database they are right)

Wasn't sure which side I had to fix. I decided to fix it in openlayers_cck.module.
The other option would have been "/openlayers/includes/behaviors/openlayers_behavior_zoomtolayer.inc".
I wasn't 100% sure because I don't know what content should be in the argument of options_form($defaults).

However, this patch fixes this issue with a one-line-change.