mtd: rename CONFIG_NAND -> CONFIG_MTD_RAW_NAND

Add more clarity by changing the Kconfig entry name.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
[trini: Re-run migration, update a few more cases]
Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
diff --git a/configs/bg0900_defconfig b/configs/bg0900_defconfig
index e8f3b5f..3925c11 100644
--- a/configs/bg0900_defconfig
+++ b/configs/bg0900_defconfig
@@ -31,7 +31,7 @@
 CONFIG_SYS_RELOC_GD_ENV_ADDR=y
 CONFIG_MXS_GPIO=y
 # CONFIG_MMC is not set
-CONFIG_NAND=y
+CONFIG_MTD_RAW_NAND=y
 CONFIG_NAND_MXS=y
 CONFIG_MII=y
 CONFIG_CONS_INDEX=0