[mlag]Fix mlag fdb not remove in kernel when remote fdb entry removed

[pettershao-ragilenetworks]

What I did
Fix mlag fdb not remove in kernel when remote fdb entry removed issue
Why I did it
Kernel fdb table entry residue
How I verified it

before modify, Kernel fdb table entry residue:

root@TOR2:/home/admin# bridge fdb show | grep 1a:00  -->>kernel Has 1a:00 entry
00:00:01:01:1a:00 dev PortChannel16 vlan 103 master Bridge static
00:00:01:00:1a:00 dev PortChannel16 vlan 101 master Bridge static
root@TOR2:/home/admin# show mac   -->>but asic db has removed already
  No.    Vlan  MacAddress         Port           Type
-----  ------  -----------------  -------------  ------
    1     101  00:00:01:00:10:12  PortChannel16  Static
    2     102  00:00:01:00:10:22  PortChannel16  Static
Total number of entries 2
root@TOR2:/home/admin# redis-cli -n 6   -->>but state db has removed already
127.0.0.1:6379[6]> keys "*FDB*"
1) "MCLAG_REMOTE_FDB_TABLE|Vlan102:00:00:01:00:10:22"
2) "MCLAG_REMOTE_FDB_TABLE|Vlan101:00:00:01:00:10:12"

after modify, every thing seems fine:

root@TOR2:/home/admin# bridge fdb show | grep 1a:00  -->>kernel Has not 1a:00 entry
root@TOR2:/home/admin# show mac   -->>asic db has removed
  No.    Vlan  MacAddress         Port           Type
-----  ------  -----------------  -------------  ------
    1     101  00:00:01:00:10:12  PortChannel16  Static
    2     102  00:00:01:00:10:22  PortChannel16  Static
Total number of entries 2
root@TOR2:/home/admin# redis-cli -n 6   -->>state db has removed 
127.0.0.1:6379[6]> keys "*FDB*"
1) "MCLAG_REMOTE_FDB_TABLE|Vlan102:00:00:01:00:10:22"
2) "MCLAG_REMOTE_FDB_TABLE|Vlan101:00:00:01:00:10:12"

Details if related

[pettershao-ragilenetworks]

@Praveen-Brcm @qiluo-msft help forward this, thanks!

[lguohan]

where is the vstest?

[lguohan]

where is the vstest?

[pettershao-ragilenetworks]

/azp run

[azure-pipelines]

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