arm64: dts: meson: add support for the ODROID-N2+

HardKernel ODROID-N2+ uses an Amlogic S922X rev. C chip capable of higher
clock speeds than the original ODROID-N2.

The rev. C support a slighly higher VDDCPU_A & VDDCPU_B voltages and supports
the same OPPs as the Amlogic A311D SoC from the same G12B family.

Suggested-by: Dongjin Kim <tobetter@hardkernel.com>
Signed-off-by: Christian Hewitt <christianshewitt@gmail.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Kevin Hilman <khilman@baylibre.com>
Acked-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Link: https://lore.kernel.org/r/20200915152432.30616-4-narmstrong@baylibre.com