i40e: broadcast filters can trigger overflow promiscuous

When adding a bunch of VLANs to all the ports on a device, it's possible
to run out of space for broadcast filters.  The driver should trigger
overflow promiscuous in this circumstance to prevent traffic from being
unexpectedly dropped.
Signed-off-by: NAlan Brady <alan.brady@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_main.c

@@ -2177,11 +2177,13 @@ i40e_aqc_broadcast_filter(struct i40e_vsi *vsi, const char *vsi_name,
 							    NULL);
 	}
 
-	if (aq_ret)
+	if (aq_ret) {
+		set_bit(__I40E_VSI_OVERFLOW_PROMISC, vsi->state);
 		dev_warn(&vsi->back->pdev->dev,
-			 "Error %s setting broadcast promiscuous mode on %s\n",
+			 "Error %s, forcing overflow promiscuous on %s\n",
 			 i40e_aq_str(hw, hw->aq.asq_last_status),
 			 vsi_name);
+	}
 
 	return aq_ret;
 }