Stop the work on suspend, otherwise it may run between our suspend method
running and the system suspending, possibly restarting the fan which
we've just stopped.

Note we already requeue the work on resume, so that we get a fresh speed
at resume.
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>