regulator: palmas: Call palmas_ldo_[read|write] in palmas_ldo_init

Current code uses wrong calls palmas_smps_[read|write] in palmas_ldo_init(),
should be palmas_ldo_[read|write] instead.

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