qeth: add query OSA address table support

Add qeth device private ioctl to query the OSA address table.
This helps debugging hw related problems.

Signed-off-by: Frank Blaschka <frank.blaschka@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/s390/net/qeth_l2_main.c b/drivers/s390/net/qeth_l2_main.c
index c129671..e5c9cf1 100644
--- a/drivers/s390/net/qeth_l2_main.c
+++ b/drivers/s390/net/qeth_l2_main.c
@@ -75,6 +75,9 @@
 			mii_data->val_out = qeth_mdio_read(dev,
 				mii_data->phy_id, mii_data->reg_num);
 		break;
+	case SIOC_QETH_QUERY_OAT:
+		rc = qeth_query_oat_command(card, rq->ifr_ifru.ifru_data);
+		break;
 	default:
 		rc = -EOPNOTSUPP;
 	}