scsi: bnx2fc: Add filters to the non-offload FCoE receive path.

Add the following filters to bnx2fc_recv_frame():

1. Filter out invalid packets
    - eth->dest_mac[3] matches FC frame's D_ID
2. Filter out packets that are not from our connected target
    - In FIP_ST_ENABLED mode
    - eth->src_mac matches fcoe_ctlr->dest_addr
3. Filter out packets where if d_id of the packet doesn't belong to
   the device when one is already assigned a port_id, only then this
   packet is dropped

Signed-off-by: Chad Dupuis <chad.dupuis@cavium.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>