mfd: toshiba: Constify struct mfd_cell where possible

As of commit 03e361b25ee8dfb1fd9b890072c23c4aae01c6c7 ("mfd: Stop setting
refcounting pointers in original mfd_cell arrays"), the "cell" parameter of
mfd_add_devices() is "const" again. Hence make all cell data passed to
mfd_add_devices() const where possible.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
diff --git a/drivers/mfd/tc3589x.c b/drivers/mfd/tc3589x.c
index 87ea51d..2cf636c 100644
--- a/drivers/mfd/tc3589x.c
+++ b/drivers/mfd/tc3589x.c
@@ -155,7 +155,7 @@
 	},
 };
 
-static struct mfd_cell tc3589x_dev_gpio[] = {
+static const struct mfd_cell tc3589x_dev_gpio[] = {
 	{
 		.name		= "tc3589x-gpio",
 		.num_resources	= ARRAY_SIZE(gpio_resources),
@@ -164,7 +164,7 @@
 	},
 };
 
-static struct mfd_cell tc3589x_dev_keypad[] = {
+static const struct mfd_cell tc3589x_dev_keypad[] = {
 	{
 		.name           = "tc3589x-keypad",
 		.num_resources  = ARRAY_SIZE(keypad_resources),