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/uDPU_defconfig b/configs/uDPU_defconfig
index e9cc822..9a97479 100644
--- a/configs/uDPU_defconfig
+++ b/configs/uDPU_defconfig
@@ -59,6 +59,7 @@
 CONFIG_MMC_SDHCI=y
 CONFIG_MMC_SDHCI_SDMA=y
 CONFIG_MMC_SDHCI_XENON=y
+CONFIG_MTD=y
 CONFIG_DM_MTD=y
 CONFIG_SF_DEFAULT_MODE=0
 CONFIG_SPI_FLASH_BAR=y