The iser initiator is the RDMA responder so it should publish to the
target the max inflight rdma read requests its local HCA can handle in
responder_resources (max_qp_rd_atom).

The iser target should take the min of that and its local HCA max
inflight oustanding rdma read requests (max_qp_init_rd_atom).

We keep initiator_depth set to 1 in order to compat with old targets.
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>