ARM: dts: meson: add u-boot.dtsi for p200 and p201

This adds *-u-boot.dtsi files for p200 and p201 boards
These are just copies of arch/arm/dts/meson-gxbb-odroidc2-u-boot.dtsi

Signed-off-by: Mohammad Rasim <mohammad.rasim96@gmail.com>
Acked-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>