drivers/net/wan/farsync.c: add missing iounmap

Free card->mem in the error-handling code since it was successfully
allocated just above.
Signed-off-by: NJulia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/wan/farsync.c

@@ -2483,6 +2483,7 @@ fst_add_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 		pr_err("Control memory remap failed\n");
 		pci_release_regions(pdev);
 		pci_disable_device(pdev);
+		iounmap(card->mem);
 		kfree(card);
 		return -ENODEV;
 	}