arm: sun8i: orangepi-pc-plus: Set EMAC activity LEDs to active high

On the Orange Pi PC Plus, the polarity of the LEDs on the RJ45 Ethernet
port were changed from active low to active high.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>