thunderbolt: Fix a leak in tb_retimer_add()

commit bec4d7c upstream.

After the device_register() succeeds, then the correct way to clean up
is to call device_unregister().  The unregister calls both device_del()
and device_put().  Since this code was only device_del() it results in
a memory leak.

Fixes: dacb128 ("thunderbolt: Add support for on-board retimers")
Cc: stable@vger.kernel.org
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/thunderbolt/retimer.c

@@ -347,7 +347,7 @@ static int tb_retimer_add(struct tb_port *port, u8 index, u32 auth_status)
 	ret = tb_retimer_nvm_add(rt);
 	if (ret) {
 		dev_err(&rt->dev, "failed to add NVM devices: %d\n", ret);
-		device_del(&rt->dev);
+		device_unregister(&rt->dev);
 		return ret;
 	}