regulator: 88pm800: fix LDO vsel_mask value

As per datasheet,
Except LDO2, all other LDO's use bit [3:0] for VOUT select.

Current code uses wrong mask value of 0x1f, So this patch
fixes it to use 0xf.

Signed-off-by: Yi Zhang <yizhang@marvell.com>
[vaibhav.hiremath@linaro.org: Updated changelog with more detailed description]
Signed-off-by: Vaibhav Hiremath <vaibhav.hiremath@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

drivers/regulator/88pm800.c

@@ -130,7 +130,7 @@ struct pm800_regulators {
 		.owner	= THIS_MODULE,					\
 		.n_voltages = ARRAY_SIZE(ldo_volt_table),		\
 		.vsel_reg	= PM800_##vreg##_VOUT,			\
-		.vsel_mask	= 0x1f,					\
+		.vsel_mask	= 0xf,					\
 		.enable_reg	= PM800_##ereg,				\
 		.enable_mask	= 1 << (ebit),				\
 		.volt_table	= ldo_volt_table,			\