kobject_init_and_add() takes reference even when it fails.  If this
function returns an error, kobject_put() must be called to properly clean
up the memory associated with the object. Previous
commit b8eb7183 ("net-sysfs: Fix reference count leak in
rx|netdev_queue_add_kobject") fixed a similar problem.

Link: https://lore.kernel.org/r/20200528030231.9082-1-wu000273@umn.eduSigned-off-by: Qiushi Wu <wu000273@umn.edu>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>