scsi: be2iscsi: Remove isr_lock and dead code

todo_mcc_cq is not needed as only MCC work is queued.
todo_cq is not used at all.
Rename functions to be consistent.

Signed-off-by: Jitendra Bhivare <jitendra.bhivare@broadcom.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>