Remove 2/3 chance of deferring Fort Ludios portal to a later level. The portal will now appear in the first vault generated past level 10, although it still has a chance of not appearing if none are.

git-svn-id: https://unnethack.svn.sourceforge.net/svnroot/unnethack/trunk@1424 f1e491ac-5ded-4967-80bf-9f4855be876a