arm64: dts: rockchip: Add support for Khadas Edge-V

Add devicetree support for Khadas Edge-V.
Khadas Edge-V is a Khadas VIM form factor Rockchip RK3399 board.

Specification
- Rockchip RK3399
- Dual-Channel 2GB/4GB LPDDR4
- SD card slot
- Onboard 16GB/32GB/128GB eMMC
- RTL8211FD 1Gbps
- AP6356S/AP6398S WiFI/BT
- HDMI Out, DP, MIPI DSI/CSI, eDP
- USB 3.0, 2.0
- USB Type C power and data
- GPIO expansion ports
- Full 4 Lane M.2 Socket
- 16MB SPI Flash
- IR
- Programmable MCU

Commit details of rk3399-khadas-edge-*.dts sync from Linux 5.3-rc2:
"arm64: dts: rockchip: Add support for Khadas Edge/Edge-V/Captain boards"
(sha1: c2aacceedc86af87428d998e23a1aca24fd8aa2e)

Signed-off-by: Nick Xie <nick@khadas.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
diff --git a/board/rockchip/evb_rk3399/MAINTAINERS b/board/rockchip/evb_rk3399/MAINTAINERS
index 10bd89a..c5b5018 100644
--- a/board/rockchip/evb_rk3399/MAINTAINERS
+++ b/board/rockchip/evb_rk3399/MAINTAINERS
@@ -12,6 +12,12 @@
 F:	configs/khadas-edge-rk3399_defconfig
 F:	arch/arm/dts/rk3399-khadas-edge-u-boot.dtsi
 
+KHADAS-EDGE-V
+M:	Nick Xie <nick@khadas.com>
+S:	Maintained
+F:	configs/khadas-edge-v-rk3399_defconfig
+F:	arch/arm/dts/rk3399-khadas-edge-v-u-boot.dtsi
+
 NANOPC-T4
 M:	Jagan Teki <jagan@amarulasolutions.com>
 S:	Maintained