pmic: pca9450: Fix control register for LDO5

pmic: pca9450: Fix control register for LDO5

For LDO5 we need to be able to check the status of the SD_VSEL input in
order to know which control register is used. Read the status of the
SD_VSEL signal via GPIO and use the correct register accordingly.

To use this, the LDO5 node in the devicetree needs the sd-vsel-gpios
property to reference the GPIO that is used to read back the SD_VSEL
status internally. Please note that the SION bit in the IOMUX must be
set if the signal is muxed as VSELECT and controlled by the USDHC
controller.

This is equivalent to the following change in Linux:

3ce6f4f943dd ("regulator: pca9450: Fix control register for LDO5")

Signed-off-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Signed-off-by: Peng Fan <peng.fan@nxp.com>