Platform: OLPC: Constify static struct regulator_ops

The only usage of it is to assign its address to the ops field in the
regulator_desc struct, which is a pointer to const struct regulator_ops.
Make it const to allow the compiler to put it in read-only memory.
Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Link: https://lore.kernel.org/r/20210206232152.58046-1-rikard.falkeborn@gmail.comSigned-off-by: Hans de Goede <hdegoede@redhat.com>

drivers/platform/olpc/olpc-ec.c

@@ -386,7 +386,7 @@ static int dcon_regulator_is_enabled(struct regulator_dev *rdev)
 	return ec->dcon_enabled ? 1 : 0;
 }
 
-static struct regulator_ops dcon_regulator_ops = {
+static const struct regulator_ops dcon_regulator_ops = {
 	.enable		= dcon_regulator_enable,
 	.disable	= dcon_regulator_disable,
 	.is_enabled	= dcon_regulator_is_enabled,