Convert CONFIG_BOARD_EARLY_INIT_F to Kconfig

This converts the following to Kconfig:
   CONFIG_BOARD_EARLY_INIT_F

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/configs/VOM405_defconfig b/configs/VOM405_defconfig
index aaaf31a..9593aea 100644
--- a/configs/VOM405_defconfig
+++ b/configs/VOM405_defconfig
@@ -6,6 +6,7 @@
 CONFIG_BOOTDELAY=3
 CONFIG_SYS_CONSOLE_INFO_QUIET=y
 CONFIG_VERSION_VARIABLE=y
+CONFIG_BOARD_EARLY_INIT_F=y
 CONFIG_CMD_I2C=y
 # CONFIG_CMD_SETEXPR is not set
 CONFIG_CMD_DHCP=y