ptp: ocp: fix resource freeing order

In the Linux kernel, the following vulnerability has been resolved: ptp: ocp: fix resource freeing order Commit a60fc3294a37 ("ptp: rework ptp_clock_unregister() to disable events") added a call to ptp_disable_all_events() which changes the configuration of pins if they support EXTTS events. In ptp_ocp_detach() pins resources are freed before ptp_clock_unregister() and it leads to use-after-free during driver removal. Fix it by changing the order of free/unregister calls. To avoid irq handler running on the other core while ptp device unregistering, call synchronize_irq() after HW is configured to stop producing irqs and no irqs are in-flight.