Common header files:
          - iscsi_ifev.h (user/kernel events).
          - iscsi_if.h (iSCSI open interface over netlink);
          - iscsi_proto.h (RFC3720 #defines and types);

          Signed-off-by: Alex Aizman <itn780@yahoo.com>
          Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com>