e1000: fix WARN_ON with mac-vlan

When adding more than 14 mac-vlan adapters on e1000 the driver
would fire a WARN_ON when adding the 15th.  The WARN_ON in this
case is completely un-necessary, as the code below the WARN_ON is
directly handling the value the WARN_ON triggered on.

CC: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/e1000/e1000_main.c

@@ -2161,8 +2161,6 @@ static void e1000_set_rx_mode(struct net_device *netdev)
 			e1000_rar_set(hw, ha->addr, i++);
 		}
 
-	WARN_ON(i == rar_entries);
-
 	netdev_for_each_mc_addr(ha, netdev) {
 		if (i == rar_entries) {
 			/* load any remaining addresses into the hash table */