Add i.MX8MP power domain handling into the driver. This is based on the
Linux GPCv2 driver state which is soon to be in Linux next.
Tested-By: Tim Harvey <tharvey@gateworks.com> #imx8mp-venice-gw74xx
Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Fabio Estevam <festevam@gmail.com>
Cc: Peng Fan <peng.fan@nxp.com>
Cc: Stefano Babic <sbabic@denx.de>
