configs: milkv_duo: Add ethernet configs

Add configs related to ethernet and ethernet boot command for Sophgo Milk-V
Duo board

Signed-off-by: Kongyang Liu <seashell11234455@gmail.com>
Reviewed-by: Leo Yu-Chi Liang <ycliang@andestech.com>
diff --git a/configs/milkv_duo_defconfig b/configs/milkv_duo_defconfig
index 28bd4b5..1738796 100644
--- a/configs/milkv_duo_defconfig
+++ b/configs/milkv_duo_defconfig
@@ -20,15 +20,19 @@
 CONFIG_CMD_MMC=y
 CONFIG_CMD_PART=y
 CONFIG_CMD_POWEROFF=y
+CONFIG_CMD_DHCP=y
+CONFIG_CMD_PXE=y
 CONFIG_CMD_FAT=y
 CONFIG_CMD_FS_GENERIC=y
 CONFIG_ENV_OVERWRITE=y
+CONFIG_NET_RANDOM_ETHADDR=y
 CONFIG_MMC=y
 CONFIG_MMC_IO_VOLTAGE=y
 CONFIG_MMC_UHS_SUPPORT=y
 CONFIG_MMC_SDHCI=y
 CONFIG_MMC_SDHCI_ADMA=y
 CONFIG_MMC_SDHCI_CV1800B=y
+CONFIG_ETH_DESIGNWARE=y
 CONFIG_SYS_NS16550=y
 CONFIG_SYS_NS16550_MEM32=y
 CONFIG_SYSRESET=y