regulator: db8500-prcmu: Set 1.8V as a fixed voltage for vsmps2

This regulator is used for system IO and is fixed to 1.8V. Let's give
consumers the option to fetch the voltage level.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Mark Brown <broonie@linaro.org>

drivers/regulator/db8500-prcmu.c

@@ -263,6 +263,8 @@ dbx500_regulator_info[DB8500_NUM_REGULATORS] = {
 			.ops	= &db8500_regulator_ops,
 			.type	= REGULATOR_VOLTAGE,
 			.owner	= THIS_MODULE,
+			.fixed_uV = 1800000,
+			.n_voltages = 1,
 		},
 		.exclude_from_power_state = true,
 	},