mtd: ensure MTD/the raw NAND core are compiled when there is a NAND flash

Both symbols must be enabled when there is a raw NAND driver
selected. Also enable them when CONFIG_CMD_NAND is selected to avoid
breaking things when we'll further rework the MTD dependency
description.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
[trini: Rebase and migrate a few more boards here]
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/configs/usb_a9263_dataflash_defconfig b/configs/usb_a9263_dataflash_defconfig
index 9ca9ca3..ca60fad 100644
--- a/configs/usb_a9263_dataflash_defconfig
+++ b/configs/usb_a9263_dataflash_defconfig
@@ -49,3 +49,4 @@
 CONFIG_ATMEL_USART=y
 CONFIG_SPI=y
 CONFIG_DM_SPI=y
+CONFIG_MTD=y