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/board/sunxi/README.nand b/board/sunxi/README.nand
index 98ebe5f..0e97316 100644
--- a/board/sunxi/README.nand
+++ b/board/sunxi/README.nand
@@ -21,7 +21,7 @@
 SPL image that is ready to be programmed directly embedding the ECCs,
 randomized, and with the necessary bits needed to reduce the number of
 bitflips. The U-Boot build system, when configured for the NAND (with
-CONFIG_NAND=y) will also generate the image sunxi-spl-with-ecc.bin
+CONFIG_MTD_RAW_NAND=y) will also generate the image sunxi-spl-with-ecc.bin
 that will have been generated by that tool.
 
 In order to flash your U-Boot image onto a board, assuming that the