board: rockchip: Add rk3308 evb support

Add support for rk3308 evaluation board.

Signed-off-by: Andy Yan <andy.yan@rock-chips.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
diff --git a/board/rockchip/evb_rk3308/Makefile b/board/rockchip/evb_rk3308/Makefile
new file mode 100644
index 0000000..05de556
--- /dev/null
+++ b/board/rockchip/evb_rk3308/Makefile
@@ -0,0 +1,7 @@
+#
+# (C) Copyright 2018 Rockchip Electronics Co., Ltd
+#
+# SPDX-License-Identifier:     GPL-2.0+
+#
+
+obj-y	+= evb_rk3308.o