Fix CFollowTrackT::Follow returning EC_NO_WAY instead of EC_RAIL_TYPE.

This can result in YAPF desyncs as this then ends up in the cache as a
ESRB_DEAD_END instead of a ESRB_RAIL_TYPE, which is problematic
when some vehicles can use the rail type but some cannot.

src/pathfinder/follow_track.hpp

@@ -145,7 +145,7 @@ struct CFollowTrackT
 			 * missing road bit, or inability to connect the
 			 * different bits due to slopes. */
 			if (IsRoadTT() && !IsTram() && TryReverse()) return true;
-			m_err = EC_NO_WAY;
+			if (m_new_td_bits == TRACKDIR_BIT_NONE) m_err = EC_NO_WAY;
 			return false;
 		}
 		if (!Allow90degTurns()) {