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/CPCI2DP_defconfig b/configs/CPCI2DP_defconfig
index 2dfd63c..eafef38 100644
--- a/configs/CPCI2DP_defconfig
+++ b/configs/CPCI2DP_defconfig
@@ -5,6 +5,7 @@
 CONFIG_BOOTDELAY=3
 CONFIG_SYS_CONSOLE_INFO_QUIET=y
 CONFIG_VERSION_VARIABLE=y
+CONFIG_BOARD_EARLY_INIT_F=y
 CONFIG_LOOPW=y
 CONFIG_CMD_I2C=y
 # CONFIG_CMD_SETEXPR is not set