RDMA/rtrs: Remove sessname and sess_kobj from rtrs_attrs

The two members are not used in the code, so remove them.

Link: https://lore.kernel.org/r/20210325153308.1214057-10-gi-oh.kim@ionos.com


Signed-off-by: Guoqing Jiang <guoqing.jiang@ionos.com>
Reviewed-by: Danil Kipnis <danil.kipnis@ionos.com>
Signed-off-by: Gioh Kim <gi-oh.kim@ionos.com>
Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>