This is a small cleanup, that also may turn error handling of
unitialized disks more readable. We don't need a separate variable to
track allocated disks, remove dr and reuse drive variable instead.
Signed-off-by: NHerton Ronaldo Krzesinski <herton.krzesinski@canonical.com>
Signed-off-by: NJiri Kosina <jkosina@suse.cz>
Signed-off-by: NJens Axboe <axboe@kernel.dk>