Convert CONFIG_BOARD_EARLY_INIT_F et al to Kconfig

This converts the following to Kconfig:
   CONFIG_BOARD_EARLY_INIT_F
   CONFIG_BOARD_EARLY_INIT_R

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/mscc_servalt_defconfig b/configs/mscc_servalt_defconfig
index 669d9f6..49d8468 100644
--- a/configs/mscc_servalt_defconfig
+++ b/configs/mscc_servalt_defconfig
@@ -15,6 +15,7 @@
 CONFIG_BOOTARGS="console=ttyS0,115200"
 CONFIG_LOGLEVEL=7
 CONFIG_DISPLAY_CPUINFO=y
+CONFIG_BOARD_EARLY_INIT_R=y
 CONFIG_SYS_PROMPT="servalt # "
 # CONFIG_CMD_BDI is not set
 # CONFIG_CMD_CONSOLE is not set