rockchip: Enable networking support on rock2 and firefly

Enable the various configuration option required to get the ethernet
interface up and running on Radxa Rock2 and Firefly.

Signed-off-by: Sjoerd Simons <sjoerd.simons@collabora.co.uk>
Signed-off-by: Romain Perier <romain.perier@collabora.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
diff --git a/configs/rock2_defconfig b/configs/rock2_defconfig
index a3b0c87..95adbdf 100644
--- a/configs/rock2_defconfig
+++ b/configs/rock2_defconfig
@@ -43,6 +43,10 @@
 CONFIG_SYS_I2C_ROCKCHIP=y
 CONFIG_MMC_DW=y
 CONFIG_MMC_DW_ROCKCHIP=y
+CONFIG_DM_ETH=y
+CONFIG_NETDEVICES=y
+CONFIG_ETH_DESIGNWARE=y
+CONFIG_GMAC_ROCKCHIP=y
 CONFIG_PINCTRL=y
 CONFIG_SPL_PINCTRL=y
 # CONFIG_SPL_PINCTRL_FULL is not set