drivers/net/bonding: Adjust constant name

AD_SHORT_TIMEOUT and AD_STATE_LACP_ACTIVITY have the same value, but
AD_STATE_LACP_ACTIVITY better reflects the intended semantics.

[ J adds: AD_STATE_LACP_ACTIVITY is a value defined by the standard, and
should be set here in accordance with 802.3ad 43.4.12; AD_SHORT_TIMEOUT
is a constant specific to the Linux 802.3ad implementation that happens
to have the same value ]

The semantic match that finds this problem is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@@
struct port_params p;
@@
* p.port_state |= AD_SHORT_TIMEOUT
// </smpl>
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Jay Vosburgh <fubar@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/bonding/bond_3ad.c

@@ -1109,7 +1109,8 @@ static void ad_rx_machine(struct lacpdu *lacpdu, struct port *port)
 			//mux machine in case of EXPIRED even if LINK_DOWN didn't arrive for the port.
 			port->partner_oper.port_state &= ~AD_STATE_SYNCHRONIZATION;
 			port->sm_vars &= ~AD_PORT_MATCHED;
-			port->partner_oper.port_state |= AD_SHORT_TIMEOUT;
+			port->partner_oper.port_state |=
+				AD_STATE_LACP_ACTIVITY;
 			port->sm_rx_timer_counter = __ad_timer_to_ticks(AD_CURRENT_WHILE_TIMER, (u16)(AD_SHORT_TIMEOUT));
 			port->actor_oper_port_state |= AD_STATE_EXPIRED;
 			break;