IB/iser: iSCSI iSER transport provider high level code

This file contains the code that registeres with the iscsi transport manager
and with the SCSI Mid Layer, where much of the provided functions to iSCSI and
SCSI are implemented in libiscsi.
Signed-off-by: Or Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>