rockchip: rk3399: Add Orangepi RK3399 support

Add initial support for Orangepi RK3399 board.

Specification
- Rockchip RK3399
- 2GB/4GB DDR3
- 16GB eMMC
- SD card slot
- RTL8211E 1Gbps
- AP6356S WiFI/BT
- HDMI In/Out, DP, MIPI DSI/CSI
- Mini PCIe
- Sensors, Keys etc
- DC12V-2A and DC5V-2A

Commit details about Linux DTS sync:
"arm64: dts: rockchip: Add support for the Orange Pi RK3399"
(sha1: d3e71487a790979057c0fdbf32f85033639c16e6)

Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
Reviewed-by: Philipp Tomsich <philipp.tomsich@theobroma-systems.com>
diff --git a/board/rockchip/evb_rk3399/MAINTAINERS b/board/rockchip/evb_rk3399/MAINTAINERS
index caad306..07ee8ce 100644
--- a/board/rockchip/evb_rk3399/MAINTAINERS
+++ b/board/rockchip/evb_rk3399/MAINTAINERS
@@ -5,3 +5,10 @@
 F:      include/configs/evb_rk3399.h
 F:      configs/evb-rk3399_defconfig
 F:      configs/firefly-rk3399_defconfig
+
+ORANGEPI-RK3399
+M:	Jagan Teki <jagan@amarulasolutions.com>
+S:	Maintained
+F:	configs/orangepi-rk3399_defconfig
+F:	arch/arm/dts/rk3399-u-boot.dtsi
+F:	arch/arm/dts/rk3399-orangepi-u-boot.dtsi