regulator: rk808: cleanup parent device usage

By overridering the device's of_node a bit earlier we can
get the GPIOs and any other DT properties from our own
device instead of relying on the parent device.

Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Link: https://lore.kernel.org/r/20230504173618.142075-13-sebastian.reichel@collabora.com


Signed-off-by: Mark Brown <broonie@kernel.org>