Convert CONFIG_NAND_MXS to Kconfig

This converts CONFIG_NAND_MXS to Kconfig.

Signed-off-by: Stefan Agner <stefan.agner@toradex.com>
diff --git a/configs/mx6sxsabreauto_defconfig b/configs/mx6sxsabreauto_defconfig
index a2c4830..43b6ab9 100644
--- a/configs/mx6sxsabreauto_defconfig
+++ b/configs/mx6sxsabreauto_defconfig
@@ -10,7 +10,6 @@
 CONFIG_CMD_GPIO=y
 CONFIG_CMD_I2C=y
 CONFIG_CMD_MMC=y
-CONFIG_CMD_NAND=y
 CONFIG_CMD_NAND_TRIMFFS=y
 CONFIG_CMD_SF=y
 CONFIG_CMD_USB=y
@@ -31,6 +30,8 @@
 CONFIG_DM_PCA953X=y
 CONFIG_DM_I2C=y
 CONFIG_DM_MMC=y
+CONFIG_NAND=y
+CONFIG_NAND_MXS=y
 CONFIG_SPI_FLASH=y
 CONFIG_SPI_FLASH_BAR=y
 CONFIG_SPI_FLASH_STMICRO=y