regulator: lp87565: Fix the initial voltage range

The latest documentation reveals that initial voltage range that is
supported is starting from 0.6V for all the PMICs belonging to lp87565
family. Fix the same.

Signed-off-by: Keerthy <j-keerthy@ti.com>
Fixes: f0168a9b ("regulator: lp87565: Add support for lp87565 PMIC regulators")
Signed-off-by: Mark Brown <broonie@kernel.org>