arm64: dts: allwinner: a64: olinuxino: add user red LED

There is a red LED marked as `GPIO_LED1` on the silkscreen and connected
to PE17 by default. So lets add this missing bit in the current hardware
description.

Signed-off-by: Petr Štetiar <ynezz@true.cz>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>