nvmet-fcloop: swap list_add_tail arguments

The newly element to be added to the list is the first argument of
list_add_tail. This fix is missing dcfad4ab ("nvmet-fcloop: swap
the list_add_tail arguments").

Fixes: 437c0b82 ("nvme-fcloop: add target to host LS request support")
Signed-off-by: Daniel Wagner <wagi@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>