mtd: rename CONFIG_MTD_DEVICE -> CONFIG_MTD

Like in Linux, just use CONFIG_MTD to compile the MTD stack.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
diff --git a/drivers/mtd/onenand/onenand_uboot.c b/drivers/mtd/onenand/onenand_uboot.c
index c15ec9d..6893394 100644
--- a/drivers/mtd/onenand/onenand_uboot.c
+++ b/drivers/mtd/onenand/onenand_uboot.c
@@ -43,7 +43,7 @@
 			puts("Flex-");
 		puts("OneNAND: ");
 
-#ifdef CONFIG_MTD_DEVICE
+#ifdef CONFIG_MTD
 		/*
 		 * Add MTD device so that we can reference it later
 		 * via the mtdcore infrastructure (e.g. ubi).