rockchip: add px30-evb board

The px30 evb is an evaluation board for the px30 together with a dsi-
connected display. This adds board and config files for it.

Signed-off-by: Heiko Stuebner <heiko.stuebner@theobroma-systems.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
diff --git a/board/rockchip/evb_px30/MAINTAINERS b/board/rockchip/evb_px30/MAINTAINERS
new file mode 100644
index 0000000..cf13f24
--- /dev/null
+++ b/board/rockchip/evb_px30/MAINTAINERS
@@ -0,0 +1,6 @@
+EVB-PX30
+M:      Kever Yang <kever.yang@rock-chips.com>
+S:      Maintained
+F:      board/rockchip/evb_px30
+F:      include/configs/evb_px30.h
+F:      configs/evb-px30_defconfig