mtd: nand: Arasan: Add subpage configuration support

Add support for disabling subpage write support via
CONFIG_SYS_NAND_NO_SUBPAGE_WRITE.

Currently the Linux Arasan driver does not support subpage writes and in
case of running UBI and accessing the same UBI volume from both U-Boot
and Linux it is required to have the same subpage write configuration
else the location of the UBI headers (EC + VID) will be misaligned
(subpage vs page) and incompatible. Hence the need for disabling
subpage write support in the U-Boot Arasan NAND driver.

Signed-off-by: Martin Lund <malu@gomspace.com>
Acked-by: Siva Durga Prasad Paladugu <siva.durga.paladugu@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
diff --git a/drivers/mtd/nand/raw/arasan_nfc.c b/drivers/mtd/nand/raw/arasan_nfc.c
index 41db9f8b..dc531cc 100644
--- a/drivers/mtd/nand/raw/arasan_nfc.c
+++ b/drivers/mtd/nand/raw/arasan_nfc.c
@@ -1201,6 +1201,10 @@
 	mtd = nand_to_mtd(nand_chip);
 	nand_set_controller_data(nand_chip, nand);
 
+#ifdef CONFIG_SYS_NAND_NO_SUBPAGE_WRITE
+	nand_chip->options |= NAND_NO_SUBPAGE_WRITE;
+#endif
+
 	/* Set the driver entry points for MTD */
 	nand_chip->cmdfunc = arasan_nand_cmd_function;
 	nand_chip->select_chip = arasan_nand_select_chip;