i40e: fix a bug in debugfs with add/del macaddr

The new code flow requires us to grab the filter list lock before
adding/deleting the filter.

Change-ID: I4eaef508ab4da2d1b2e23f20f2a78d931d5b6aeb
Signed-off-by: NAnjali Singhai Jain <anjali.singhai@intel.com>
Tested-by: NAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: NJeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/i40e/i40e_debugfs.c

@@ -1137,7 +1137,9 @@ static ssize_t i40e_dbg_command_write(struct file *filp,
 			goto command_write_done;
 		}
 
+		spin_lock_bh(&vsi->mac_filter_list_lock);
 		f = i40e_add_filter(vsi, ma, vlan, false, false);
+		spin_unlock_bh(&vsi->mac_filter_list_lock);
 		ret = i40e_sync_vsi_filters(vsi, true);
 		if (f && !ret)
 			dev_info(&pf->pdev->dev,
@@ -1174,7 +1176,9 @@ static ssize_t i40e_dbg_command_write(struct file *filp,
 			goto command_write_done;
 		}
 
+		spin_lock_bh(&vsi->mac_filter_list_lock);
 		i40e_del_filter(vsi, ma, vlan, false, false);
+		spin_unlock_bh(&vsi->mac_filter_list_lock);
 		ret = i40e_sync_vsi_filters(vsi, true);
 		if (!ret)
 			dev_info(&pf->pdev->dev,