regulator: max8998: Constify regulator_ops

These regulator_ops variables never need to be modified, make them const so
compiler can put them to .rodata.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/drivers/regulator/max8998.c b/drivers/regulator/max8998.c
index 271bb73..43b69eb 100644
--- a/drivers/regulator/max8998.c
+++ b/drivers/regulator/max8998.c
@@ -427,7 +427,7 @@ static int max8998_set_voltage_buck_time_sel(struct regulator_dev *rdev,
 	return 0;
 }
 
-static struct regulator_ops max8998_ldo_ops = {
+static const struct regulator_ops max8998_ldo_ops = {
 	.list_voltage		= regulator_list_voltage_linear,
 	.map_voltage		= regulator_map_voltage_linear,
 	.is_enabled		= max8998_ldo_is_enabled,
@@ -437,7 +437,7 @@ static struct regulator_ops max8998_ldo_ops = {
 	.set_voltage_sel	= max8998_set_voltage_ldo_sel,
 };
 
-static struct regulator_ops max8998_buck_ops = {
+static const struct regulator_ops max8998_buck_ops = {
 	.list_voltage		= regulator_list_voltage_linear,
 	.map_voltage		= regulator_map_voltage_linear,
 	.is_enabled		= max8998_ldo_is_enabled,
@@ -448,7 +448,7 @@ static struct regulator_ops max8998_buck_ops = {
 	.set_voltage_time_sel	= max8998_set_voltage_buck_time_sel,
 };
 
-static struct regulator_ops max8998_others_ops = {
+static const struct regulator_ops max8998_others_ops = {
 	.is_enabled		= max8998_ldo_is_enabled,
 	.enable			= max8998_ldo_enable,
 	.disable		= max8998_ldo_disable,