firewire: core: optimize card shutdown

This fixes a regression by "firewire: keep highlevel drivers attached
during brief connection loss": There were 2 seconds unnecessary waiting
added to the shutdown procedure of each controller.

We use card->link as status flag to signal the device handler that there
is no use to wait for a come-back.

Signed-off-by: Stefan Richter <[e-mail]>

drivers/firewire/fw-card.c

···
 	fw_core_initiate_bus_reset(card, 1);
 
 	mutex_lock(&card_mutex);
-	list_del(&card->link);
+	list_del_init(&card->link);
 	mutex_unlock(&card_mutex);
 
 	/* Set up the dummy driver. */

drivers/firewire/fw-device.c

···
 		container_of(work, struct fw_device, work.work);
 	int minor = MINOR(device->device.devt);
 
-	if (time_is_after_jiffies(device->card->reset_jiffies + SHUTDOWN_DELAY)) {
+	if (time_is_after_jiffies(device->card->reset_jiffies + SHUTDOWN_DELAY)
+	    && !list_empty(&device->card->link)) {
 		schedule_delayed_work(&device->work, SHUTDOWN_DELAY);
 		return;
 	}
···
 		if (atomic_xchg(&device->state,
 				FW_DEVICE_GONE) == FW_DEVICE_RUNNING) {
 			PREPARE_DELAYED_WORK(&device->work, fw_device_shutdown);
-			schedule_delayed_work(&device->work, SHUTDOWN_DELAY);
+			schedule_delayed_work(&device->work,
+				list_empty(&card->link) ? 0 : SHUTDOWN_DELAY);
 		}
 		break;
 	}