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/mx53ard_defconfig b/configs/mx53ard_defconfig
index 7690765..f0ecb4d 100644
--- a/configs/mx53ard_defconfig
+++ b/configs/mx53ard_defconfig
@@ -19,6 +19,7 @@
 CONFIG_ENV_IS_IN_MMC=y
 CONFIG_SYS_RELOC_GD_ENV_ADDR=y
 CONFIG_FSL_ESDHC_IMX=y
+CONFIG_MTD=y
 CONFIG_MTD_RAW_NAND=y
 CONFIG_SYS_NAND_USE_FLASH_BBT=y
 CONFIG_NAND_MXC=y