soc: nordic: nrf54h: transition from gpd to zephyr pinctrl and pds

Transition nrf54h away from the soc specific gpd
(global power domain) driver which mixed power domains, pinctrl
and gpio pin retention into a non scalable solution, forcing soc
specific logic to bleed into nrf drivers.

The new solution uses zephyrs PM_DEVICE based power domains to
properly model the hardware layout of device and pin power domains,
and moves pin retention logic out of drivers into pinctrl and
gpio, which are the components which manage pins (pads).

Signed-off-by: Bjarki Arge Andreasen <bjarki.andreasen@nordicsemi.no>