IB/iser: iSCSI iSER transport provider header file

iSER (iSCSI Extensions for RDMA) transport provider driver for the iSCSI
initiator, whose other parts (under drivers/scsi) are scsi_transport_iscsi
- the transport management module, iscsi_tcp - the TCP transport provider
module and libiscsi - a kernel library (module) implementing functionality
needed by both TCP and iSER transports. iSER is both a provider of the iSCSI
transport api and a SCSI low level driver.

This file contains internal data structures and non static service functions.
Signed-off-by: Or Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>