ARM: dts: sun8i: Add Orange Pi Plus support

The Orange Pi Plus is a SBC based on the Allwinner H3 SoC
with 8GB eMMC, multiple USB ports through a USB hub chip, SATA through
a USB-SATA bridge, one uSD slot, a 10/100/1000M ethernet port,
WiFi, HDMI, headphone jack, IR receiver, a microphone, a CSI connector
and a 40-pin GPIO header.

Signed-off-by: Jens Kuske <jenskuske@gmail.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>