FLAT-DOOR-F and FLAT-F handle entering incorrectly

[eriktorbjorn]

Here's how FLAT-DOOR-F handles entering:

           (<ENTERING?>
        <COND (<HERE? THALL>
               <DO-WALK ,P?EAST>)
              (T
               <DO-WALK ,P?WEST>)>
        T)

Here's how FLAT-F handles it:

           (<ENTERING?>
        <DO-WALK ,P?EAST>
        T)

However, IN-FLAT is south of THALL, not east, so this code probably reflects an earlier version of the game's map.