net: ena: fix: Free napi resources when ena_up() fails

ena_up() calls ena_init_napi() but does not call ena_del_napi() in
case of failure. This causes a segmentation fault upon rmmod when
netif_napi_del() is called. Fix this bug by calling ena_del_napi()
before returning error from ena_up().

Fixes: 1738cd3 ("net: ena: Add a driver for Amazon Elastic Network Adapters (ENA)")
Signed-off-by: Arthur Kiyanovski <akiyano@amazon.com>
Signed-off-by: Sameeh Jubran <sameehj@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/amazon/ena/ena_netdev.c

@@ -1825,6 +1825,7 @@ static int ena_up(struct ena_adapter *adapter)
 err_setup_tx:
 	ena_free_io_irq(adapter);
 err_req_irq:
+	ena_del_napi(adapter);
 
 	return rc;
 }