Convert CONFIG_OF_EMBED to Kconfig

This converts the following to Kconfig:
   CONFIG_OF_EMBED

Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Rick Chen <rick@andestech.com>
diff --git a/configs/adp-ae3xx_defconfig b/configs/adp-ae3xx_defconfig
index 2183712..3fa00fb 100644
--- a/configs/adp-ae3xx_defconfig
+++ b/configs/adp-ae3xx_defconfig
@@ -24,6 +24,7 @@
 CONFIG_CMD_EXT2=y
 CONFIG_CMD_FAT=y
 CONFIG_OF_CONTROL=y
+CONFIG_OF_EMBED=y
 CONFIG_ENV_OVERWRITE=y
 CONFIG_ENV_IS_IN_SPI_FLASH=y
 CONFIG_SYS_RELOC_GD_ENV_ADDR=y