bna: Fix Filter Add Del

Change Details:
 - bna_rx_mcast_listset() API first looks at free_q only and not at other
   pending Qs rendering it non-deterministic of giving an upper limit.
   Modify bna_rx_mcast_listset() implementation to not use only half of the
   limit.
 - Allocate and initialize queue for deleting
 - Segregate the adding and deleting process by using separate queues.
 - The filter framework in bna does not let adding addresses to its max capacity
   due to asynchronous operations involved.
   Provide a synchronous option to set a given list.

Signed-off-by: Rasesh Mody <rmody@brocade.com>
Signed-off-by: David S. Miller <davem@davemloft.net>