ARM: make use of nand_set/get_controller_data() helpers

New helpers have been added to avoid directly accessing chip->field. Use
them where appropriate.
Signed-off-by: NBoris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: NBrian Norris <computersforpeace@gmail.com>

arch/arm/mach-ixp4xx/ixdp425-setup.c

@@ -77,7 +77,7 @@ static void
 ixdp425_flash_nand_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl)
 {
 	struct nand_chip *this = mtd_to_nand(mtd);
-	int offset = (int)this->priv;
+	int offset = (int)nand_get_controller_data(this);
 
 	if (ctrl & NAND_CTRL_CHANGE) {
 		if (ctrl & NAND_NCE) {
@@ -88,7 +88,7 @@ ixdp425_flash_nand_cmd_ctrl(struct mtd_info *mtd, int cmd, unsigned int ctrl)
 
 		offset = (ctrl & NAND_CLE) ? IXDP425_NAND_CMD_BYTE : 0;
 		offset |= (ctrl & NAND_ALE) ? IXDP425_NAND_ADDR_BYTE : 0;
-		this->priv = (void *)offset;
+		nand_set_controller_data(this, (void *)offset);
 	}
 
 	if (cmd != NAND_CMD_NONE)