Convert CONFIG_SYS_NAND_ONFI_DETECTION to Kconfig

This converts the following to Kconfig:
   CONFIG_SYS_NAND_ONFI_DETECTION

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/am335x_evm_spiboot_defconfig b/configs/am335x_evm_spiboot_defconfig
index bf5f7d2..f6006c5 100644
--- a/configs/am335x_evm_spiboot_defconfig
+++ b/configs/am335x_evm_spiboot_defconfig
@@ -62,6 +62,7 @@
 CONFIG_MMC_OMAP_HS=y
 CONFIG_MTD=y
 CONFIG_MTD_RAW_NAND=y
+CONFIG_SYS_NAND_ONFI_DETECTION=y
 CONFIG_SYS_NAND_PAGE_SIZE=0x800
 CONFIG_SYS_NAND_OOBSIZE=0x40
 # CONFIG_SPL_NAND_AM33XX_BCH is not set