regulator: tps65090: Add support for LDO regulators

TPS65090 supports the two LDOs, LDO1 and LDO2. These are
always ON regulators. The output on these LDOs are available
once the input voltage available for these LDOs.
Add support for these LDOs regulators.

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>