svcrdma: Remove post_send_wr

Clean up: Now that the send_wr is part of the svc_rdma_send_ctxt,
svc_rdma_post_send_wr is nearly empty.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/net/sunrpc/xprtrdma/svc_rdma_backchannel.c b/net/sunrpc/xprtrdma/svc_rdma_backchannel.c
index 95e3351..40f5e4a 100644
--- a/net/sunrpc/xprtrdma/svc_rdma_backchannel.c
+++ b/net/sunrpc/xprtrdma/svc_rdma_backchannel.c
@@ -139,7 +139,8 @@ static int svc_rdma_bc_sendto(struct svcxprt_rdma *rdma,
 	 * the rq_buffer before all retransmits are complete.
 	 */
 	get_page(virt_to_page(rqst->rq_buffer));
-	ret = svc_rdma_post_send_wr(rdma, ctxt, 0);
+	ctxt->sc_send_wr.opcode = IB_WR_SEND;
+	ret = svc_rdma_send(rdma, &ctxt->sc_send_wr);
 	if (ret)
 		goto out_unmap;