regulator: pfuze100: Don't allocate an invalid gpio

Previously, the PFUZE100 would try to allocate gpio0 io0 because
config.ena_gpio defaults to 0, which can be a valid GPIO.  To prevent this
from happening, set this parameter to -EINVAL.
Signed-off-by: Sean Cross <xobs@kosagi.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

drivers/regulator/pfuze100-regulator.c

@@ -506,6 +506,7 @@ static int pfuze100_regulator_probe(struct i2c_client *client,
 		config.init_data = init_data;
 		config.driver_data = pfuze_chip;
 		config.of_node = match_of_node(i);
+		config.ena_gpio = -EINVAL;
 
 		pfuze_chip->regulators[i] =
 			devm_regulator_register(&client->dev, desc, &config);