pktcdvd: removing device does not remove its sysfs dir

This is the counterpart to cba76717
("pktcdvd: remove broken dev_t export of class devices").  Device is not
registered using dev_t, so it should not be destroyed using device_destroy
which looks up the device by dev_t.  This will fail and adding the device
again will fail with the "duplicate name" error.  This is fixed using
device_unregister instead of device_destroy.
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Cc: Peter Osterlund <petero2@telia.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/block/pktcdvd.c

@@ -322,7 +322,7 @@ static void pkt_sysfs_dev_remove(struct pktcdvd_device *pd)
 	pkt_kobj_remove(pd->kobj_stat);
 	pkt_kobj_remove(pd->kobj_wqueue);
 	if (class_pktcdvd)
-		device_destroy(class_pktcdvd, pd->pkt_dev);
+		device_unregister(pd->dev);
 }