Fix patch #4768. Node behavior was broken taken in account if the tile was known
or not.

Reported by Marko Lindqvist (cazfi@gna) and me

See bug #22217 & bug #22224

git-svn-id: svn://svn.gna.org/svn/freeciv/trunk@25213 a0f10bec-cc02-0410-94fc-a9cfff90b4cd