This property isn't needed and not yet used anywhere. The swap-dx-lanes
property is perfectly fine for doing the swap on the upstream port
lanes.

CC: stable@vger.kernel.org #5.2
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Link: https://lore.kernel.org/r/20190719084407.28041-2-l.stach@pengutronix.deSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>