ARM: dts: sun8i-h2-plus-bananapi-m2-zero: Fix led polarity

ARM: dts: sun8i-h2-plus-bananapi-m2-zero: Fix led polarity

The PWR-LED on the bananapi m2 zero board is on when gpio PL10 is low.
This has been verified on a board and in the schematics [1].

[1]: http://wiki.banana-pi.org/Banana_Pi_BPI-M2_ZERO#Documents

Fixes: 8b8061fcbfae ("ARM: dts: sun8i: h2+: add support for Banana Pi M2 Zero board")
Signed-off-by: Vincent Stehlé <vincent.stehle@laposte.net>
Cc: Icenowy Zheng <icenowy@aosc.io>
Cc: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>