rockchip: rk3328: Add support for FriendlyARM NanoPi R2S

This adds support for the NanoPi R2S from FriendlyArm.

Rockchip RK3328 SoC
1GB DDR4 RAM
Gigabit Ethernet (WAN)
Gigabit Ethernet (USB3) (LAN)
USB 2.0 Host Port
MicroSD slot
Reset button
WAN - LAN - SYS LED

Signed-off-by: David Bauer <mail@david-bauer.net>
Reviewed-by: Kever <Yang&lt;kever.yang@rock-chips.com>