regulator: max8649: Constify regulator_desc

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/drivers/regulator/max8649.c b/drivers/regulator/max8649.c
index 824c650..aa91ec6 100644
--- a/drivers/regulator/max8649.c
+++ b/drivers/regulator/max8649.c
@@ -207,7 +207,7 @@
 
 };
 
-static struct regulator_desc dcdc_desc = {
+static const struct regulator_desc dcdc_desc = {
 	.name		= "max8649",
 	.ops		= &max8649_dcdc_ops,
 	.type		= REGULATOR_VOLTAGE,