ice: Fix max VLANs available for VF

Legacy VLAN implementation allows for untrusted VF to have 8 VLAN
filters, not counting VLAN 0 filters. Current VLAN_V2 implementation
lowers available filters for VF, by counting in VLAN 0 filter for both
TPIDs.
Fix this by counting only non zero VLAN filters.
Without this patch, untrusted VF would not be able to access 8 VLAN
filters.

Fixes: cc71de8 ("ice: Add support for VIRTCHNL_VF_OFFLOAD_VLAN_V2")
Signed-off-by: Przemyslaw Patynowski <przemyslawx.patynowski@intel.com>
Signed-off-by: Mateusz Palczewski <mateusz.palczewski@intel.com>
Tested-by: Marek Szlosek <marek.szlosek@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

Author: Kaaame

drivers/net/ethernet/intel/ice/ice_virtchnl.c

@@ -2948,7 +2948,8 @@ ice_vc_validate_add_vlan_filter_list(struct ice_vsi *vsi,
 				     struct virtchnl_vlan_filtering_caps *vfc,
 				     struct virtchnl_vlan_filter_list_v2 *vfl)
 {
-	u16 num_requested_filters = vsi->num_vlan + vfl->num_elements;
+	u16 num_requested_filters = ice_vsi_num_non_zero_vlans(vsi) +
+		vfl->num_elements;
 
 	if (num_requested_filters > vfc->max_filters)
 		return false;