regulator: make the dummy regulator's print_constraint more helpful

This prevents the output of just

	dummy:

in the boot log. Now it says:

	regulator-dummy: no parameters

which at least doesn't make it look like an accidental printk and also doesn't
only use "dummy" which could mean anything.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/drivers/regulator/dummy.c b/drivers/regulator/dummy.c
index 86f655c..03a1d7c 100644
--- a/drivers/regulator/dummy.c
+++ b/drivers/regulator/dummy.c
@@ -30,7 +30,7 @@
 static struct regulator_ops dummy_ops;
 
 static struct regulator_desc dummy_desc = {
-	.name = "dummy",
+	.name = "regulator-dummy",
 	.id = -1,
 	.type = REGULATOR_VOLTAGE,
 	.owner = THIS_MODULE,