pinctrl: Declare operation structures as const

The pinconf, pinctrl and pinmux operation structures hold function
pointers that are never modified. Declare them as const.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/pinctrl/pinctrl-samsung.c b/drivers/pinctrl/pinctrl-samsung.c
index f206df1..3475b92 100644
--- a/drivers/pinctrl/pinctrl-samsung.c
+++ b/drivers/pinctrl/pinctrl-samsung.c
@@ -214,7 +214,7 @@
 }
 
 /* list of pinctrl callbacks for the pinctrl core */
-static struct pinctrl_ops samsung_pctrl_ops = {
+static const struct pinctrl_ops samsung_pctrl_ops = {
 	.get_groups_count	= samsung_get_group_count,
 	.get_group_name		= samsung_get_group_name,
 	.get_group_pins		= samsung_get_group_pins,
@@ -357,7 +357,7 @@
 }
 
 /* list of pinmux callbacks for the pinmux vertical in pinctrl core */
-static struct pinmux_ops samsung_pinmux_ops = {
+static const struct pinmux_ops samsung_pinmux_ops = {
 	.get_functions_count	= samsung_get_functions_count,
 	.get_function_name	= samsung_pinmux_get_fname,
 	.get_function_groups	= samsung_pinmux_get_groups,
@@ -468,7 +468,7 @@
 }
 
 /* list of pinconfig callbacks for pinconfig vertical in the pinctrl code */
-static struct pinconf_ops samsung_pinconf_ops = {
+static const struct pinconf_ops samsung_pinconf_ops = {
 	.pin_config_get		= samsung_pinconf_get,
 	.pin_config_set		= samsung_pinconf_set,
 	.pin_config_group_get	= samsung_pinconf_group_get,