nvmet-auth: add missing goto in nvmet_setup_auth()

There's a goto missing in nvmet_setup_auth(), causing a kernel oops
when nvme_auth_extract_key() fails.
Reported-by: Tal Lossos <tallossos@gmail.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

drivers/nvme/target/auth.c

@@ -196,6 +196,7 @@ int nvmet_setup_auth(struct nvmet_ctrl *ctrl)
 	if (IS_ERR(ctrl->ctrl_key)) {
 		ret = PTR_ERR(ctrl->ctrl_key);
 		ctrl->ctrl_key = NULL;
+		goto out_free_hash;
 	}
 	pr_debug("%s: using ctrl hash %s key %*ph\n", __func__,
 		 ctrl->ctrl_key->hash > 0 ?