regulator: da9063: Select maximum current in specific range for set_current_limit

Selecting the minimal value is only true for voltage regulators.
For current regulators the maximum in the given range should be
selected instead.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Steve Twiss <stwiss.opensource@diasemi.com>
Signed-off-by: Mark Brown <broonie@kernel.org>