rockchip: add support for rk3288 PopMetal board

PopMetal is a rockchip rk3288 based board made by ChipSpark, which has
many interface such as HDMI, VGA, USB, micro-SD card, WiFi, Audio and
Gigabit Ethernet.

Signed-off-by: Ziyuan Xu <xzy.xu@rock-chips.com>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/board/chipspark/popmetal_rk3288/Kconfig b/board/chipspark/popmetal_rk3288/Kconfig
new file mode 100644
index 0000000..a5f4043
--- /dev/null
+++ b/board/chipspark/popmetal_rk3288/Kconfig
@@ -0,0 +1,15 @@
+if TARGET_POPMETAL_RK3288
+
+config SYS_BOARD
+	default "popmetal_rk3288"
+
+config SYS_VENDOR
+	default "chipspark"
+
+config SYS_CONFIG_NAME
+	default "popmetal_rk3288"
+
+config BOARD_SPECIFIC_OPTIONS # dummy
+	def_bool y
+
+endif