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: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/wan/farsync.c b/drivers/net/wan/farsync.c
index ebb9f24..1a62318 100644
--- a/drivers/net/wan/farsync.c
+++ b/drivers/net/wan/farsync.c
@@ -2483,6 +2483,7 @@
 		pr_err("Control memory remap failed\n");
 		pci_release_regions(pdev);
 		pci_disable_device(pdev);
+		iounmap(card->mem);
 		kfree(card);
 		return -ENODEV;
 	}