net: bonding: bond_main: Document 'proto' and rename 'new_active' parameters

Fixes the following W=1 kernel build warning(s):

 drivers/net/bonding/bond_main.c:329: warning: Function parameter or member 'proto' not described in 'bond_vlan_rx_add_vid'
 drivers/net/bonding/bond_main.c:362: warning: Function parameter or member 'proto' not described in 'bond_vlan_rx_kill_vid'
 drivers/net/bonding/bond_main.c:964: warning: Function parameter or member 'new_active' not described in 'bond_change_active_slave'
 drivers/net/bonding/bond_main.c:964: warning: Excess function parameter 'new' description in 'bond_change_active_slave'

Cc: Jay Vosburgh <j.vosburgh@gmail.com>
Cc: Veaceslav Falico <vfalico@gmail.com>
Cc: Andy Gospodarek <andy@greyhouse.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Thomas Davis <tadavis@lbl.gov>
Cc: netdev@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: David S. Miller <davem@davemloft.net>