Fix fast leave bug when multiple LAN ports joined one group.

	- In fast leave mode, leave a multicast group on upstream only
	  when all LAN ports have left the group. The member ports
	  checking is via parsing bridge MDB.

    - Removed the specific query during fast leave, which is a known
	  error in the first commit for fast leave.

    - In fast leave mode, the fast leave flag in kernel bridge driver
	  is set on all member interfaces of bridge br-lan.

    - Disabled the IGMP general query on br-lan in kernel bridge
	  driver, because it is taken by mcproxy.