rockchip: Add support for Raxda Rock 2

This board includes an RK3288 SoC on a SOM. It can be mounted on a
base-board which provides a wide range of peripherals.

So far this is verified to boot to a prompt from a microSD card. The serial
console works as well as HDMI.

Thanks to Tom Cubie for sending me a board.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/arm/dts/Makefile b/arch/arm/dts/Makefile
index 7706b41..641510c 100644
--- a/arch/arm/dts/Makefile
+++ b/arch/arm/dts/Makefile
@@ -22,6 +22,7 @@
 dtb-$(CONFIG_ARCH_ROCKCHIP) += \
 	rk3288-firefly.dtb \
 	rk3288-jerry.dtb \
+	rk3288-rock2-square.dtb \
 	rk3036-sdk.dtb
 dtb-$(CONFIG_TEGRA) += tegra20-harmony.dtb \
 	tegra20-medcom-wide.dtb \