zebra: fix for unexpected fdb entry showing up during ifdown/ifup events

zebra: fix for unexpected fdb entry showing up during ifdown/ifup events

Ticket: 2674793
Testing Done:  precommit, evpn-min and evpn-smoke

The problem in this case is whenever we are triggering ifdown
followed by ifup of bridge, we see that remote mac entries
are programmed with vlan-1 in the fdb from zebra and never cleaned up.
bridge has vlan_default_pvid 1 which means any port that gets added
will initially have vlan 1 which then gets deleted by ifupdown2 and
the proper vlan gets added.

The problem lies in zebra where we are not cleaning up the remote
macs during vlan change.

Fix is to uninstall the remote macs and then install them
during vlan change.

Signed-off-by: Stephen Worley <sworley@nvidia.com>