scsi: be2iscsi: Check all zeroes IP before issuing IOCTL

Redefine FW IP types.
Before issuing IOCTL to clear IP, check if IP is all zeroes.
All zeroes IP implies IP is not set in FW so FW fails that IOCTL.

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>