regulator: dts: enable soft-start and ramp delay for the OLinuXino Lime2

The OLinuXino Lime2 has a big capacitor on its LDO3 output. It is
actually too large, causing the PMIC to shutdown when toggling the LDO3.

By enabling soft-start and ramp delay we increase the time for the
capacitor to charge lowering the current drain on the power regulator.

Signed-off-by: Olliver Schinagl <oliver@schinagl.nl>
Signed-off-by: Priit Laes <plaes@plaes.org>
Signed-off-by: Mark Brown <broonie@kernel.org>