armv7: make gpmc_cfg const

Signed-off-by: Ladislav Michl <ladis@linux-mips.org>
[trini: Adapt am33xx, duovero, omap_zoom1]
Signed-off-by: Tom Rini <trini@konsulko.com>

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/drivers/mtd/nand/omap_gpmc.c b/drivers/mtd/nand/omap_gpmc.c
index 67f293d..6e201d6 100644
--- a/drivers/mtd/nand/omap_gpmc.c
+++ b/drivers/mtd/nand/omap_gpmc.c
@@ -264,7 +264,8 @@
 {
 	struct nand_chip *chip = mtd_to_nand(mtd);
 	struct omap_nand_info *info = nand_get_controller_data(chip);
-	uint32_t *ptr, val = 0;
+	const uint32_t *ptr;
+	uint32_t val = 0;
 	int8_t i = 0, j;
 
 	switch (info->ecc_scheme) {