rockchip: rk3288: enable rockusb support on rk3288 based device

this patch enable rockusb support on rk3288 based device.

Signed-off-by: Eddie Cai <eddie.cai.linux@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/configs/fennec-rk3288_defconfig b/configs/fennec-rk3288_defconfig
index 008776e..d76e8c4 100644
--- a/configs/fennec-rk3288_defconfig
+++ b/configs/fennec-rk3288_defconfig
@@ -78,3 +78,8 @@
 CONFIG_USE_TINY_PRINTF=y
 CONFIG_CMD_DHRYSTONE=y
 CONFIG_ERRNO_STR=y
+CONFIG_USB_GADGET_DOWNLOAD=y
+CONFIG_USB_GADGET_VBUS_DRAW=0
+CONFIG_G_DNL_MANUFACTURER="Rockchip"
+CONFIG_G_DNL_VENDOR_NUM=0x2207
+CONFIG_G_DNL_PRODUCT_NUM=0x320a