TS-7680: linux-6.6.y: Unable to reboot the system

[ts-kris]

The TS-7680 imported in to 6.6.y mostly cleanly, however reboot functionality has broken.

Some history/notes:
In 4.9, the ts_wdt driver would register itself as the highest priority reset handler when it loaded. In 5.10 however, some changes to the machine files for mxs CPUs caused the kernel to use the mxs registered restart handler and bypasses the notifier/restart chain. This overrode the arm_pm_restart variable that the mxs machine file set. In 6.6, neither of these work for some reason. The Arm restart process no longer uses arm_pm_restart and will always use the restart notifier chain. However, despite ts_wdt registering itself as a restart handler, at the highest priority, the WDT restart handler never gets called.

Eventually, the platform will reboot with the WDT timing out as it is not closed at poweroff.