netxen: handle firmware load errors

Unwind allocations and release file firmware when
when firmware load fails.

Signed-off-by: Dhananjay Phadke <dhananjay@netxen.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/netxen/netxen_nic_init.c b/drivers/net/netxen/netxen_nic_init.c
index 04e36f2..534994d 100644
--- a/drivers/net/netxen/netxen_nic_init.c
+++ b/drivers/net/netxen/netxen_nic_init.c
@@ -905,6 +905,7 @@
 {
 	if (adapter->fw)
 		release_firmware(adapter->fw);
+	adapter->fw = NULL;
 }
 
 int netxen_init_dummy_dma(struct netxen_adapter *adapter)