configs: move CONFIG_MTD in defconfigs when set in arch includes

Let's be consistent and always declare CONFIG_MTD from the defconfig
file when needed.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Boris Brezillon <boris.brezillon@bootlin.com>
diff --git a/configs/turris_mox_defconfig b/configs/turris_mox_defconfig
index fafc471..b88cc4b 100644
--- a/configs/turris_mox_defconfig
+++ b/configs/turris_mox_defconfig
@@ -49,6 +49,7 @@
 CONFIG_MMC_SDHCI=y
 CONFIG_MMC_SDHCI_SDMA=y
 CONFIG_MMC_SDHCI_XENON=y
+CONFIG_MTD=y
 CONFIG_SF_DEFAULT_MODE=0
 CONFIG_SF_DEFAULT_SPEED=20000000
 CONFIG_SPI_FLASH_MACRONIX=y
diff --git a/include/configs/mvebu_armada-37xx.h b/include/configs/mvebu_armada-37xx.h
index 8b54bee..024a971 100644
--- a/include/configs/mvebu_armada-37xx.h
+++ b/include/configs/mvebu_armada-37xx.h
@@ -56,7 +56,6 @@
  * SPI Flash configuration
  */
 
-#define CONFIG_MTD			/* needed for mtdparts commands */
 #define CONFIG_MTD_PARTITIONS		/* required for UBI partition support */
 
 /* Environment in SPI NOR flash */
diff --git a/include/configs/socfpga_stratix10_socdk.h b/include/configs/socfpga_stratix10_socdk.h
index 4e7c300..a10cbec 100644
--- a/include/configs/socfpga_stratix10_socdk.h
+++ b/include/configs/socfpga_stratix10_socdk.h
@@ -62,7 +62,6 @@
 /*#define CONFIG_ENV_IS_IN_SPI_FLASH*/
 
 #ifndef CONFIG_SPL_BUILD
-#define CONFIG_MTD
 #define CONFIG_MTD_PARTITIONS
 #define MTDIDS_DEFAULT			"nor0=ff705000.spi.0"
 #endif /* CONFIG_SPL_BUILD */