RDMA/ib_srpt: Unify checking rdma_cm_id condition in srpt_cm_req_recv()

RDMA/ib_srpt: Unify checking rdma_cm_id condition in srpt_cm_req_recv()

Although rdma_cm_id and ib_cm_id passing to srpt_cm_req_recv() are
exclusive currently, all other checking condition are using rdma_cm_id.
So unify the 'if' condition to make the code more clear.

Link: https://lore.kernel.org/r/1659336226-2-1-git-send-email-lizhijian@fujitsu.com
Signed-off-by: Li Zhijian <lizhijian@fujitsu.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>