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/configs/colibri_imx7_emmc_defconfig b/configs/colibri_imx7_emmc_defconfig
index 6ba2647..4fe1e36 100644
--- a/configs/colibri_imx7_emmc_defconfig
+++ b/configs/colibri_imx7_emmc_defconfig
@@ -58,6 +58,7 @@
 CONFIG_DM_MMC=y
 CONFIG_SUPPORT_EMMC_BOOT=y
 CONFIG_FSL_USDHC=y
+CONFIG_MTD=y
 CONFIG_PHYLIB=y
 CONFIG_PHY_MICREL=y
 CONFIG_PHY_MICREL_KSZ8XXX=y