[SCSI] bnx2i: Added handling for unsupported iSCSI offload hba

The hba will now be unregistered and freed when iSCSI offload
is not supported by the NIC.

Signed-off-by: Eddie Wai <eddie.wai@broadcom.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>