x86: coreboot: Convert to use more dm drivers

Move to driver model for RTC, USB and ETH on coreboot.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/configs/coreboot-x86_defconfig b/configs/coreboot-x86_defconfig
index ebaf86b..e95f96d 100644
--- a/configs/coreboot-x86_defconfig
+++ b/configs/coreboot-x86_defconfig
@@ -14,10 +14,13 @@
 CONFIG_OF_CONTROL=y
 CONFIG_DM_PCI=y
 CONFIG_SPI_FLASH=y
-CONFIG_NETDEVICES=y
+CONFIG_DM_ETH=y
 CONFIG_E1000=y
 CONFIG_DM_TPM=y
 CONFIG_TPM_TIS_LPC=y
+CONFIG_USB=y
+CONFIG_DM_USB=y
+CONFIG_DM_RTC=y
 CONFIG_USE_PRIVATE_LIBGCC=y
 CONFIG_SYS_VSNPRINTF=y
 CONFIG_TPM=y