Coming up from sublevels should not put players in mountains

git-svn-id: http://svn.net-core.org/repos/t-engine4@6015 51575b47-30f0-44d4-a5cc-537603b46e54

game/modules/tome/class/Game.lua

@@ -786,6 +786,7 @@ function _M:changeLevelReal(lev, zone, params)
 			if lev > old_lev and not params.force_down then x, y = self.level.default_up.x, self.level.default_up.y
 			else x, y = self.level.default_down.x, self.level.default_down.y
 			end
+			if not x then x, y = self.level.default_up.x, self.level.default_up.y end
 		end
 
 		-- Check if there is already an actor at that location, if so move it