mtd: nand: Move arasan nand driver to driver model

Make changes to arasan nand driver to move it to driver model.
Select DM_MTD if arasan nand driver is selected.

Signed-off-by: Ashok Reddy Soma <ashok.reddy.soma@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
diff --git a/drivers/mtd/nand/raw/Kconfig b/drivers/mtd/nand/raw/Kconfig
index 16165f8..ec17653 100644
--- a/drivers/mtd/nand/raw/Kconfig
+++ b/drivers/mtd/nand/raw/Kconfig
@@ -236,6 +236,7 @@
 config NAND_ARASAN
 	bool "Configure Arasan Nand"
 	select SYS_NAND_SELF_INIT
+	select DM_MTD
 	imply CMD_NAND
 	help
 	  This enables Nand driver support for Arasan nand flash