Fix signalled bridge/tunnel not always being redrawn on (un)reservation.

src/pbs.cpp

@@ -126,6 +126,7 @@ bool TryReserveRailTrack(TileIndex tile, Track t, bool trigger_stations)
 			if (GetTunnelBridgeTransportType(tile) == TRANSPORT_RAIL && !GetTunnelBridgeReservationTrackBits(tile)) {
 				SetTunnelBridgeReservation(tile, true);
 				if (IsTunnelBridgeExit(tile) && IsTunnelBridgePBS(tile)) SetTunnelBridgeExitGreen(tile, true);
+				MarkTileDirtyByTile(tile);
 				return true;
 			}
 			break;
@@ -181,6 +182,7 @@ void UnreserveRailTrack(TileIndex tile, Track t)
 			if (GetTunnelBridgeTransportType(tile) == TRANSPORT_RAIL) {
 				SetTunnelBridgeReservation(tile, false);
 				if (IsTunnelBridgeExit(tile) && IsTunnelBridgePBS(tile)) SetTunnelBridgeExitGreen(tile, false);
+				MarkTileDirtyByTile(tile);
 			}
 			break;
 

src/train_cmd.cpp

@@ -3231,6 +3231,7 @@ static bool CheckTrainStayInWormHolePathReserve(Train *t, TileIndex tile)
 		if (reserved == TRACKDIR_BIT_NONE) {
 			/* next tile is not reserved, so reserve the exit tile */
 			SetTunnelBridgeReservation(tile, true);
+			MarkTileDirtyByTile(tile);
 		}
 	}
 	bool ok = TryPathReserve(t);