[MCLAG] Portsorch don't handle "traffic_disable" in APP DB LAG table

[chenkelly]

According sonic-net/SONiC#596,
MCLAG_Enhancements_HLD.md#3222-app_lag_table

;Add one new attribute to existing LAG_TABLE to control whether traffic collection and distribution should be disabled for all LAG member ports.
traffic_disable = "true"/"false" ;default is false

Producer is MclagSyncd Consumer, but portsorch don't handle this field in doLagTask (#1331)
https://github.com/Azure/sonic-swss/blob/master/orchagent/portsorch.cpp#L3580
Should we support this traffic distribution mode for LAG?

syslog

Mar 04 08:41:40.563841 2022 sonic NOTICE iccpd#mclagsyncd: :- mclagsyncd_set_traffic_disable: Set traffic enable for PortChannel8
Mar 04 08:41:40.820173 2022 sonic NOTICE iccpd#mclagsyncd: :- mclagsyncd_set_traffic_disable: Set traffic disable for PortChannel8

We setup MCLAG environment.
Active

root@sonic:~# mclagdctl dump state -i 1
The MCLAG's keepalive is: OK
MCLAG info sync is: incomplete
Domain id: 1
Local Ip: 192.168.50.1
Peer Ip: 192.168.50.2
Peer Link Interface: PortChannel4094
Keepalive time: 1
sesssion Timeout : 30
Peer Link Mac: 68:21:5f:f2:9f:d4
System Mac: 68:21:5f:f2:9f:d4
Gateway Mac: Not Configured
Role: Active
MCLAG Interface: PortChannel8
Loglevel: NOTICE

Standby

root@sonic:~# mclagdctl dump state -i 1
The MCLAG's keepalive is: OK
MCLAG info sync is: completed
Domain id: 1
Local Ip: 192.168.50.2
Peer Ip: 192.168.50.1
Peer Link Interface: PortChannel4094
Keepalive time: 1
sesssion Timeout : 30
Peer Link Mac: 90:3c:b3:6a:c9:ba
System Mac: 90:3c:b3:6a:c9:ba
Gateway Mac: Not Configured
Role: Standby
MCLAG Interface: PortChannel8
Loglevel: NOTICE

To check mclag member status.
Active

root@sonic:~# mclagdctl dump portlist local -i 1
......
Ifindex: 68
Type: PortChannel
PortName: PortChannel8
MAC: 68:21:5f:f2:9f:d4
IPv4Address: 0.0.0.0
Prefixlen: 32
IPv6Address: ::
Prefixlen: 0
State: Up
Admin State: Up
IsL3Interface: No
MemberPorts: Ethernet8
PortchannelIsUp: 1
IsIsolateWithPeerlink: No
IsTrafficDisable: No
VlanList: 201

---

Standby

root@sonic:~# mclagdctl dump portlist local -i 1
......
Ifindex: 68
Type: PortChannel
PortName: PortChannel8
MAC: 68:21:5f:f2:9f:d4
IPv4Address: 0.0.0.0
Prefixlen: 32
IPv6Address: ::
Prefixlen: 0
State: Up
Admin State: Up
IsL3Interface: No
MemberPorts: Ethernet8
PortchannelIsUp: 1
IsIsolateWithPeerlink: Yes
IsTrafficDisable: Yes
VlanList: 201