regulator: palmas: model SMPS10 as two regulators

SMPS10 has two outputs OUT1 and OUT2 and have one input IN1.
SMPS10-OUT2 is connected to SMPS10-IN1 and can be configured either
in BOOST mode or BYPASS mode. regulator_enable of SMPS10-OUT2 configures
it in BOOST mode. For BYPASS mode regulator_allow_bypass() API can be
used. SMPS10-OUT1 is connected to SMPS10-OUT2 and can be enabled using
regulator_enable().

[ axel.lin@ingics.com : Simplify regulator_desc setting for SMPS10_[OUT1|OUT2]

Signed-off-by: J Keerthy <j-keerthy@ti.com>
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@linaro.org>