regulator: fan53555: enable vin supply

The regulator can be supplied by a parent regulator through its vin pin,
so add the supply_name for it.

Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/drivers/regulator/fan53555.c b/drivers/regulator/fan53555.c
index 714fd9a..c912ba7 100644
--- a/drivers/regulator/fan53555.c
+++ b/drivers/regulator/fan53555.c
@@ -207,6 +207,7 @@
 	struct regulator_desc *rdesc = &di->desc;
 
 	rdesc->name = "fan53555-reg";
+	rdesc->supply_name = "vin";
 	rdesc->ops = &fan53555_regulator_ops;
 	rdesc->type = REGULATOR_VOLTAGE;
 	rdesc->n_voltages = FAN53555_NVOLTAGES;