The bridge forwards the multicast packets to all the
interfaces attached the bridge.
When the STA network interface receives such packets
from bridge and send it to the AP, it is echoed back
from the BSS.
These packets are not intended for the bridge as it
will lead to looping.
Add a check to detect and drop such packets when
received back from the BSS.
Change-Id: I5a4a2a3e015df2b9c78de405d7d917216baed051
CRs-Fixed: 2997189