BD70528MWV is an ultra-low Iq general purpose single-chip power
management IC for battery-powered portable devices.

Add support for controlling 3 bucks and 3 LDOs present in
ROHM BD70528.
Signed-off-by: NMatti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Signed-off-by: NMark Brown <broonie@kernel.org>