nand: arasan: Select CONFIG_SYS_NAND_SELF_INIT

The Arasan NFC driver requires the self-init mode,
so it should select it.

Instead of having the config header define the macro,
it's cleaner to select the option at the Kconfig level.

Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
diff --git a/drivers/mtd/nand/Kconfig b/drivers/mtd/nand/Kconfig
index 78a39ab..97ec6cf 100644
--- a/drivers/mtd/nand/Kconfig
+++ b/drivers/mtd/nand/Kconfig
@@ -123,6 +123,7 @@
 
 config NAND_ARASAN
 	bool "Configure Arasan Nand"
+	select SYS_NAND_SELF_INIT
 	imply CMD_NAND
 	help
 	  This enables Nand driver support for Arasan nand flash