qed: fix assignment of n_rq_elems to incorrect params field

Currently n_rq_elems is being assigned to params.elem_size instead of the
field params.num_elems.  Coverity is detecting this as a double assingment
to params.elem_size and reporting this as an usused value on the first
assignment.  Fix this.

Addresses-Coverity: ("Unused value")
Fixes: b6db3f71 ("qed: simplify chain allocation with init params struct")
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Acked-by: NAlexander Lobakin <alobakin@marvell.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/infiniband/hw/qedr/verbs.c

@@ -1923,7 +1923,7 @@ qedr_roce_create_kernel_qp(struct qedr_dev *dev,
 	in_params->sq_pbl_ptr = qed_chain_get_pbl_phys(&qp->sq.pbl);
 
 	params.intended_use = QED_CHAIN_USE_TO_CONSUME_PRODUCE;
-	params.elem_size = n_rq_elems;
+	params.num_elems = n_rq_elems;
 	params.elem_size = QEDR_RQE_ELEMENT_SIZE;
 
 	rc = dev->ops->common->chain_alloc(dev->cdev, &qp->rq.pbl, &params);