This patch adds setting our drv->queue = NULL back in deregister_disk.  The
drv->queue is part of our controller struct.  blk_cleanup_queue works only
on the queue in the gendisk struct.
Signed-off-by: Mike Miller <mike.miller@hp.com>
Cc: Jens Axboe <axboe@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>