Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Copy head to stable/9 as part of 9.0-RELEASE release cycle.

Approved by: re (implicit)

- Add full support for header / data digests.
- Increase target limit from 4 to 64; this limit will be removed entirely
at a later time.
- Improve recovery from lost network connections.
- Fix some potential deadlocks and a serious memory leak.
- Fix incorrect use of MH_ALIGN (instead of M_ALIGN), which makes no
practical difference, but triggers a KASSERT with INVARIANTS.
- Fix some warnings in iscontrol(8) and improve the man page somewhat.

Submitted by: Daniel Braniss <danny@cs.huji.ac.il>
Sponsored by: Dansk Scanning A/S, Data Robotics Inc.

pukeText is an internal function so define it as static rather than
exporting it.

MFC after: 1 month

Big update to the iSCSI initiator code. Highlights include IPv6 support,
many bugs fixes, many more performance improvements.

Submitted by: Danny Braniss

M sbin/iscontrol/iscsi.conf.5
M sbin/iscontrol/iscontrol.8
M sbin/iscontrol/iscontrol.h
M sbin/iscontrol/config.c
M sbin/iscontrol/fsm.c
M sbin/iscontrol/login.c
M sbin/iscontrol/pdu.c
M sbin/iscontrol/misc.c
M sbin/iscontrol/auth_subr.c
M sbin/iscontrol/iscontrol.c
M sys/dev/iscsi/initiator/isc_cam.c
M sys/dev/iscsi/initiator/iscsi.h
M sys/dev/iscsi/initiator/isc_soc.c
M sys/dev/iscsi/initiator/iscsi_subr.c
M sys/dev/iscsi/initiator/iscsivar.h
M sys/dev/iscsi/initiator/isc_subr.c
M sys/dev/iscsi/initiator/iscsi.c
M sys/dev/iscsi/initiator/isc_sm.c

Introduce Danny Braniss' iSCSI initiator, version 2.0.99. Please read the
included man pages on how to use it. This code is still somewhat experimental
but has been successfully tested on a number of targets. Many thanks to
Danny for contributing this.

Approved by: re