regulator: tps6507x: Use regulator_map_voltage_ascend

All regulators have ascendant voltage list in this driver.
Use regulator_map_voltage_ascend for them.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
1 file changed