i40e: fix the calculation of VFs mac addresses

num_mac should be increased only after the call to i40e_add_mac_filter().

Fixes: 5f527ba9 ("i40e: Limit the number of MAC and VLAN addresses that can be added for VFs")
Signed-off-by: Zijie Pan <zijie.pan@6wind.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Reviewed-by: Tushar Dave <tushar.n.dave@oracle.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c

@@ -2218,7 +2218,7 @@ static int i40e_vc_add_mac_addr_msg(struct i40e_vf *vf, u8 *msg, u16 msglen)
 		struct i40e_mac_filter *f;
 
 		f = i40e_find_mac(vsi, al->list[i].addr);
-		if (!f)
+		if (!f) {
 			f = i40e_add_mac_filter(vsi, al->list[i].addr);
 
 			if (!f) {
@@ -2232,6 +2232,7 @@ static int i40e_vc_add_mac_addr_msg(struct i40e_vf *vf, u8 *msg, u16 msglen)
 				vf->num_mac++;
 			}
 		}
+	}
 	spin_unlock_bh(&vsi->mac_filter_hash_lock);
 
 	/* program the updated filter list */