iw_cxgb4: Fix error return code in c4iw_rdev_open()

Fix to return error code -ENOMEM from the __get_free_page() error
handling case instead of 0, as done elsewhere in this function.

Fixes: 05eb2389 ("cxgb4/iw_cxgb4: Doorbell Drop Avoidance Bug Fixes")
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Acked-by: NSteve Wise <swise@opengridcomputing.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

drivers/infiniband/hw/cxgb4/device.c

@@ -828,8 +828,10 @@ static int c4iw_rdev_open(struct c4iw_rdev *rdev)
 	}
 	rdev->status_page = (struct t4_dev_status_page *)
 			    __get_free_page(GFP_KERNEL);
-	if (!rdev->status_page)
+	if (!rdev->status_page) {
+		err = -ENOMEM;
 		goto destroy_ocqp_pool;
+	}
 	rdev->status_page->qp_start = rdev->lldi.vr->qp.start;
 	rdev->status_page->qp_size = rdev->lldi.vr->qp.size;
 	rdev->status_page->cq_start = rdev->lldi.vr->cq.start;