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-mxs.c b/drivers/pinctrl/pinctrl-mxs.c
index 23af9f1..b45c4eb 100644
--- a/drivers/pinctrl/pinctrl-mxs.c
+++ b/drivers/pinctrl/pinctrl-mxs.c
@@ -158,7 +158,7 @@
 	kfree(map);
 }
 
-static struct pinctrl_ops mxs_pinctrl_ops = {
+static const struct pinctrl_ops mxs_pinctrl_ops = {
 	.get_groups_count = mxs_get_groups_count,
 	.get_group_name = mxs_get_group_name,
 	.get_group_pins = mxs_get_group_pins,
@@ -219,7 +219,7 @@
 	return 0;
 }
 
-static struct pinmux_ops mxs_pinmux_ops = {
+static const struct pinmux_ops mxs_pinmux_ops = {
 	.get_functions_count = mxs_pinctrl_get_funcs_count,
 	.get_function_name = mxs_pinctrl_get_func_name,
 	.get_function_groups = mxs_pinctrl_get_func_groups,
@@ -319,7 +319,7 @@
 		seq_printf(s, "0x%lx", config);
 }
 
-static struct pinconf_ops mxs_pinconf_ops = {
+static const struct pinconf_ops mxs_pinconf_ops = {
 	.pin_config_get = mxs_pinconf_get,
 	.pin_config_set = mxs_pinconf_set,
 	.pin_config_group_get = mxs_pinconf_group_get,