register_blkdev() is called before pci_register_driver() in skd_init()
so unregister_blkdev() should be called after pci_unregister_driver()
in skd_exit(). Fix it.
Cc: Akhil Bhansali <abhansali@stec-inc.com> Cc: Jeff Moyer <jmoyer@redhat.com> Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>