regulator fixed: Do not report enumaratable voltages if there are none

If used as a dummy voltage provider the fixed regulator should
not set n_voltages to make the core accept the device.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
1 file changed