loop: don't call loop_lookup before adding a loop device

loop_add returns the right error if the slot wasn't available.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210623145908.92973-5-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
1 file changed