regulator: rt5033: Add RT5033 Regulator device driver

This patch add device driver of Richtek RT5033 PMIC.
The driver support multiple regulator like LDO and synchronous Buck.
The integrated synchronous buck converter is designed to provide 0.6 A
application with high efficiency. Two LDOs are integrated. One safe LDO is
for 60mA and the other one LDO is for 150 mA.

Cc: Liam Girdwood <lgirdwood@gmail.com>
Cc: Mark Brown <broonie@kernel.org>
Signed-off-by: Beomho Seo <beomho.seo@samsung.com>
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>