Use NewGRF depot gfx even when GRF does not define overlays

diff -r 6c34330a82a0 src/rail_cmd.cpp
--- a/src/rail_cmd.cpp  Sun Aug 21 14:59:05 2011 +0000
+++ b/src/rail_cmd.cpp  Sun Aug 28 21:09:14 2011 +0200
@@ -2284,9 +2284,6 @@
                    default: break;
                }
            }
-
-           int depot_sprite = GetCustomRailSprite(rti, ti->tile, RTSG_DEPOT);
-           relocation = depot_sprite != 0 ? depot_sprite - SPR_RAIL_DEPOT_SE_1 : rti->GetRailtypeSpriteOffset();
        } else {
            /* PBS debugging, draw reserved tracks darker */
            if (_game_mode != GM_MENU && _settings_client.gui.show_track_reservation && HasDepotReservation(ti->tile)) {
@@ -2298,9 +2295,10 @@
                    default: break;
                }
            }
+       }

-           relocation = rti->GetRailtypeSpriteOffset();
-       }
+       int depot_sprite = GetCustomRailSprite(rti, ti->tile, RTSG_DEPOT);
+       relocation = depot_sprite != 0 ? depot_sprite - SPR_RAIL_DEPOT_SE_1 : rti->GetRailtypeSpriteOffset();

        if (HasCatenaryDrawn(GetRailType(ti->tile))) DrawCatenary(ti);