board: rockchip: Add rk3568 evb support

Add support for rk3568 evaluation board.

Signed-off-by: Joseph Chen <chenjh@rock-chips.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
diff --git a/board/rockchip/evb_rk3568/MAINTAINERS b/board/rockchip/evb_rk3568/MAINTAINERS
new file mode 100644
index 0000000..b6ea498
--- /dev/null
+++ b/board/rockchip/evb_rk3568/MAINTAINERS
@@ -0,0 +1,6 @@
+EVB-RK3568
+M:      Joseph Chen <chenjh@rock-chips.com>
+S:      Maintained
+F:      board/rockchip/evb_rk3568
+F:      include/configs/evb_rk3568.h
+F:      configs/evb-rk3568_defconfig