regulator: da903x: Fix list voltage for da9030 ldo14

da903x_list_voltage does not return correct voltage for da9030 ldo14.
Implement da9030_list_ldo14_voltage to return correct voltage for da9030 ldo14.

Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>