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/ls1046ardb_emmc_defconfig b/configs/ls1046ardb_emmc_defconfig
index e5402a2..06759db 100644
--- a/configs/ls1046ardb_emmc_defconfig
+++ b/configs/ls1046ardb_emmc_defconfig
@@ -69,6 +69,7 @@
 CONFIG_FSL_ESDHC=y
 CONFIG_MTD=y
 CONFIG_MTD_RAW_NAND=y
+CONFIG_SYS_NAND_ONFI_DETECTION=y
 # CONFIG_SPI_FLASH_BAR is not set
 # CONFIG_SPI_FLASH_USE_4K_SECTORS is not set
 CONFIG_PHYLIB=y