regulator: gpio: Constify regulator_ops

gpio_regulator_voltage_ops and gpio_regulator_current_ops should never
change, make them const.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

drivers/regulator/gpio-regulator.c

@@ -124,7 +124,7 @@ static int gpio_regulator_set_current_limit(struct regulator_dev *dev,
 	return 0;
 }
 
-static struct regulator_ops gpio_regulator_voltage_ops = {
+static const struct regulator_ops gpio_regulator_voltage_ops = {
 	.get_voltage = gpio_regulator_get_value,
 	.set_voltage = gpio_regulator_set_voltage,
 	.list_voltage = gpio_regulator_list_voltage,
@@ -220,7 +220,7 @@ of_get_gpio_regulator_config(struct device *dev, struct device_node *np,
 	return config;
 }
 
-static struct regulator_ops gpio_regulator_current_ops = {
+static const struct regulator_ops gpio_regulator_current_ops = {
 	.get_current_limit = gpio_regulator_get_value,
 	.set_current_limit = gpio_regulator_set_current_limit,
 };