RDMA/erdma: Correct the max_qp and max_cq capacities of the device

QP0 in HW is used for CMDQ, and the rest is for RDMA QPs. So the actual
max_qp capacity reported to core should be max_qp (reported by HW) - 1.
So does max_cq.

Fixes: 1550557 ("RDMA/erdma: Add verbs implementation")
Link: https://lore.kernel.org/all/20220810014320.88026-1-chengyou@linux.alibaba.com
Signed-off-by: Cheng Xu <chengyou@linux.alibaba.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>

Author: hz-cheng

drivers/infiniband/hw/erdma/erdma_verbs.c

@@ -280,7 +280,7 @@ int erdma_query_device(struct ib_device *ibdev, struct ib_device_attr *attr,
 	attr->vendor_id = PCI_VENDOR_ID_ALIBABA;
 	attr->vendor_part_id = dev->pdev->device;
 	attr->hw_ver = dev->pdev->revision;
-	attr->max_qp = dev->attrs.max_qp;
+	attr->max_qp = dev->attrs.max_qp - 1;
 	attr->max_qp_wr = min(dev->attrs.max_send_wr, dev->attrs.max_recv_wr);
 	attr->max_qp_rd_atom = dev->attrs.max_ord;
 	attr->max_qp_init_rd_atom = dev->attrs.max_ird;
@@ -291,7 +291,7 @@ int erdma_query_device(struct ib_device *ibdev, struct ib_device_attr *attr,
 	attr->max_send_sge = dev->attrs.max_send_sge;
 	attr->max_recv_sge = dev->attrs.max_recv_sge;
 	attr->max_sge_rd = dev->attrs.max_sge_rd;
-	attr->max_cq = dev->attrs.max_cq;
+	attr->max_cq = dev->attrs.max_cq - 1;
 	attr->max_cqe = dev->attrs.max_cqe;
 	attr->max_mr = dev->attrs.max_mr;
 	attr->max_pd = dev->attrs.max_pd;