platform/surface: aggregator: Do not return uninitialized value

The status variable in ssam_nf_refcount_disable_free() is only set when
the reference count equals zero. Otherwise, it is returned
uninitialized. Fix this by always initializing status to zero.
Reported-by: kernel test robot <lkp@intel.com>
Fixes: 640ee17199e4 ("platform/surface: aggregator: Allow enabling of events without notifiers")
Signed-off-by: Maximilian Luz <luzmaximilian@gmail.com>
Link: https://lore.kernel.org/r/20210604210907.25738-2-luzmaximilian@gmail.comSigned-off-by: Hans de Goede <hdegoede@redhat.com>

drivers/platform/surface/aggregator/controller.c

@@ -2228,7 +2228,7 @@ static int ssam_nf_refcount_disable_free(struct ssam_controller *ctrl,
 	const struct ssam_event_registry reg = entry->key.reg;
 	const struct ssam_event_id id = entry->key.id;
 	struct ssam_nf *nf = &ctrl->cplt.event.notif;
-	int status;
+	int status = 0;
 
 	lockdep_assert_held(&nf->lock);