Convert CONFIG_SYS_NAND_NO_SUBPAGE_WRITE to Kconfig

This converts the following to Kconfig:
   CONFIG_SYS_NAND_NO_SUBPAGE_WRITE

Signed-off-by: Tom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/mtd/nand/raw/Kconfig b/drivers/mtd/nand/raw/Kconfig
index 0e42841..3585031 100644
--- a/drivers/mtd/nand/raw/Kconfig
+++ b/drivers/mtd/nand/raw/Kconfig
@@ -41,6 +41,10 @@
 	help
 	  Enable the BBT (Bad Block Table) usage.
 
+config SYS_NAND_NO_SUBPAGE_WRITE
+	bool "Disable subpage write support"
+	depends on NAND_ARASAN || NAND_DAVINCI || NAND_KIRKWOOD
+
 config NAND_ATMEL
 	bool "Support Atmel NAND controller"
 	select SYS_NAND_SELF_INIT