Convert CONFIG_NAND_FSL_ELBC et al to Kconfig

This converts the following to Kconfig:
   CONFIG_NAND_FSL_ELBC
   CONFIG_NAND_FSL_IFC

Note that a number of PowerPC platforms had previously enabled
CONFIG_NAND_FSL_ELBC without CONFIG_MTD_RAW_NAND, and now they no longer
enable the option, reducing the size of a few functions.

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/ls2080aqds_SECURE_BOOT_defconfig b/configs/ls2080aqds_SECURE_BOOT_defconfig
index 64d10ec..4f1302a 100644
--- a/configs/ls2080aqds_SECURE_BOOT_defconfig
+++ b/configs/ls2080aqds_SECURE_BOOT_defconfig
@@ -51,6 +51,7 @@
 CONFIG_SYS_FLASH_USE_BUFFER_WRITE=y
 CONFIG_SYS_FLASH_CFI=y
 CONFIG_MTD_RAW_NAND=y
+CONFIG_NAND_FSL_IFC=y
 CONFIG_SYS_NAND_ONFI_DETECTION=y
 CONFIG_DM_SPI_FLASH=y
 CONFIG_PHYLIB=y