pinctrl: qcom: use restart_notifier mechanism for ps_hold
By converting to the restart_notifier mechanism for restart, we allow
for other mechanisms, like the watchdog, to be used for restart in the
case where PS_HOLD has failed to reset the chip.
Since this mechanism may be one of several mechanisms registered, change
the post-ps_hold write timeout to be a more reasonable 1 second instead
of 10 seconds.
Choose priority 128, as according to documentation, this mechanism "is
sufficient to restart the entire system".