RDMA/cxgb3: Fix iwch_create_cq() off-by-one error

The cxbg3 driver is unnecessarily decreasing the number of CQ entries by
one when creating a CQ.  This will cause the CQ not to have as many
entries as requested by the user if the user requests a power of 2 size.
Signed-off-by: Jon Mason <jon@opengridcomputing.com>
Acked-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

drivers/infiniband/hw/cxgb3/iwch_provider.c

@@ -189,7 +189,7 @@ static struct ib_cq *iwch_create_cq(struct ib_device *ibdev, int entries, int ve
 		return ERR_PTR(-ENOMEM);
 	}
 	chp->rhp = rhp;
-	chp->ibcq.cqe = (1 << chp->cq.size_log2) - 1;
+	chp->ibcq.cqe = 1 << chp->cq.size_log2;
 	spin_lock_init(&chp->lock);
 	atomic_set(&chp->refcnt, 1);
 	init_waitqueue_head(&chp->wait);