IB/mlx5: Fix decision on using MAD_IFC

Fix the condition that dictates when MAD_IFC should be used. According
to firmware specifications, MAD_IFC commands must be used only if the
ib_virt capability is off.

Signed-off-by: Eli Cohen <eli@mellanox.com>
Reviewed-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
diff --git a/drivers/infiniband/hw/mlx5/main.c b/drivers/infiniband/hw/mlx5/main.c
index 5afbb69..73cb633 100644
--- a/drivers/infiniband/hw/mlx5/main.c
+++ b/drivers/infiniband/hw/mlx5/main.c
@@ -283,7 +283,7 @@
 
 static int mlx5_use_mad_ifc(struct mlx5_ib_dev *dev)
 {
-	return !dev->mdev->issi;
+	return !MLX5_CAP_GEN(dev->mdev, ib_virt);
 }
 
 enum {