Codechange: Use TileAddBy(Diag)Dir when possible.

src/pathfinder/follow_track.hpp

@@ -219,8 +219,7 @@ protected:
 		}
 
 		/* normal or station tile, do one step */
-		TileIndexDiff diff = TileOffsByDiagDir(m_exitdir);
-		m_new_tile = TILE_ADD(m_old_tile, diff);
+		m_new_tile = TileAddByDiagDir(m_old_tile, m_exitdir);
 
 		/* special handling for stations */
 		if (IsRailTT() && HasStationTileRail(m_new_tile)) {

src/pathfinder/yapf/yapf_ship.cpp

@@ -69,7 +69,7 @@ public:
 		}
 
 		/* move back to the old tile/trackdir (where ship is coming from) */
-		TileIndex src_tile = TILE_ADD(tile, TileOffsByDiagDir(ReverseDiagDir(enterdir)));
+		TileIndex src_tile = TileAddByDiagDir(tile, ReverseDiagDir(enterdir));
 		Trackdir trackdir = v->GetVehicleTrackdir();
 		assert(IsValidTrackdir(trackdir));