usb: host: ehci-sched: try to turn on io watchdog as long as periodic_count > 0

usb: host: ehci-sched: try to turn on io watchdog as long as periodic_count > 0

If initially isoc_count = 0, periodic_count > 0 and the io watchdog is
not started (e.g. just timed out), then the io watchdog may not run after
submitting isoc urbs and enable_periodic(). The isoc urbs may not complete
forever if the controller had already stopped periodic schedule.

This will try to call turn_on_io_watchdog() for each enable_periodic() to
ensure the io watchdog functions properly.

Signed-off-by: Xu Yang <xu.yang_2@nxp.com>
Reviewed-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20230809065327.952368-1-xu.yang_2@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>