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/uniphier_v7_defconfig b/configs/uniphier_v7_defconfig
index 19701c2..4ac1f94 100644
--- a/configs/uniphier_v7_defconfig
+++ b/configs/uniphier_v7_defconfig
@@ -47,6 +47,7 @@
 CONFIG_MTD=y
 CONFIG_MTD_RAW_NAND=y
 CONFIG_NAND_DENALI_DT=y
+CONFIG_SYS_NAND_ONFI_DETECTION=y
 CONFIG_SPL_NAND_DENALI=y
 CONFIG_NAND_DENALI_SPARE_AREA_SKIP_BYTES=8
 CONFIG_SNI_AVE=y