power: imx8-power-domain: Set DM_FLAG_DEFAULT_PD_CTRL_OFF flag

power: imx8-power-domain: Set DM_FLAG_DEFAULT_PD_CTRL_OFF flag

If without this flag, calling dev_power_domain_ctrl will iteratively remove
the power domain device will causes iteratively power off parent PD. This is
not expected by imx8-power-domain-legacy driver. Power off parent PD is
controlled by the driver internally.

So set DM_FLAG_DEFAULT_PD_CTRL_OFF to avoid such issue

Signed-off-by: Ye Li <ye.li@nxp.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>