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-tegra.c b/drivers/pinctrl/pinctrl-tegra.c
index f195d77..2fa9bc6 100644
--- a/drivers/pinctrl/pinctrl-tegra.c
+++ b/drivers/pinctrl/pinctrl-tegra.c
@@ -316,7 +316,7 @@
 	return 0;
 }
 
-static struct pinctrl_ops tegra_pinctrl_ops = {
+static const struct pinctrl_ops tegra_pinctrl_ops = {
 	.get_groups_count = tegra_pinctrl_get_groups_count,
 	.get_group_name = tegra_pinctrl_get_group_name,
 	.get_group_pins = tegra_pinctrl_get_group_pins,
@@ -401,7 +401,7 @@
 	pmx_writel(pmx, val, g->mux_bank, g->mux_reg);
 }
 
-static struct pinmux_ops tegra_pinmux_ops = {
+static const struct pinmux_ops tegra_pinmux_ops = {
 	.get_functions_count = tegra_pinctrl_get_funcs_count,
 	.get_function_name = tegra_pinctrl_get_func_name,
 	.get_function_groups = tegra_pinctrl_get_func_groups,
@@ -676,7 +676,7 @@
 }
 #endif
 
-static struct pinconf_ops tegra_pinconf_ops = {
+static const struct pinconf_ops tegra_pinconf_ops = {
 	.pin_config_get = tegra_pinconf_get,
 	.pin_config_set = tegra_pinconf_set,
 	.pin_config_group_get = tegra_pinconf_group_get,