RDMA/rtrs: Call kobject_put in the failure path

Per the comment of kobject_init_and_add, we need to free the memory
by call kobject_put.

Fixes: 215378b8 ("RDMA/rtrs: client: sysfs interface functions")
Fixes: 91b11610 ("RDMA/rtrs: server: sysfs interface functions")
Link: https://lore.kernel.org/r/20201217141915.56989-8-jinpu.wang@cloud.ionos.com


Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Reviewed-by: Md Haris Iqbal <haris.iqbal@cloud.ionos.com>
Reviewed-by: Gioh Kim <gi-oh.kim@cloud.ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>