mlxsw: constify address in mlxsw_sp_port_dev_addr_set

Argument comes from netdev->dev_addr directly, it needs a const.
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlxsw/spectrum.c

@@ -303,7 +303,7 @@ int mlxsw_sp_port_admin_status_set(struct mlxsw_sp_port *mlxsw_sp_port,
 }
 
 static int mlxsw_sp_port_dev_addr_set(struct mlxsw_sp_port *mlxsw_sp_port,
-				      unsigned char *addr)
+				      const unsigned char *addr)
 {
 	struct mlxsw_sp *mlxsw_sp = mlxsw_sp_port->mlxsw_sp;
 	char ppad_pl[MLXSW_REG_PPAD_LEN];