RDMA/usnic: Suppress a compiler warning

This patch avoids that the following compiler warning is reported when
building with gcc 8 and W=1:

drivers/infiniband/hw/usnic/usnic_fwd.c:95:2: warning: 'strncpy' output may be truncated copying 16 bytes from a string of length 20 [-Wstringop-truncation]
  strncpy(ufdev->name, netdev_name(ufdev->netdev),
  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    sizeof(ufdev->name) - 1);
    ~~~~~~~~~~~~~~~~~~~~~~~~
Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

drivers/infiniband/hw/usnic/usnic_fwd.c

@@ -92,8 +92,8 @@ struct usnic_fwd_dev *usnic_fwd_dev_alloc(struct pci_dev *pdev)
 	ufdev->pdev = pdev;
 	ufdev->netdev = pci_get_drvdata(pdev);
 	spin_lock_init(&ufdev->lock);
-	strncpy(ufdev->name, netdev_name(ufdev->netdev),
-			sizeof(ufdev->name) - 1);
+	BUILD_BUG_ON(sizeof(ufdev->name) != sizeof(ufdev->netdev->name));
+	strcpy(ufdev->name, ufdev->netdev->name);
 
 	return ufdev;
 }

drivers/infiniband/hw/usnic/usnic_fwd.h

@@ -57,7 +57,7 @@ struct usnic_fwd_dev {
 	char				mac[ETH_ALEN];
 	unsigned int			mtu;
 	__be32				inaddr;
-	char				name[IFNAMSIZ+1];
+	char				name[IFNAMSIZ];
 };
 
 struct usnic_fwd_flow {