MFC r281532 (by delphij): Eliminate unused headers.

MFC r279589: Fix handling of queued text and logout requests.

While it may have little sense, text and logout requests can be queued.
If they are, they consume cmdsn, so we should increment our conn_cmdsn.

MFC r278322: Add support for multiple portal groups per target.

This change allows multiple "portal-group" options to be specified per
target. Each of them may include new optional auth-group name parameter
to override per-target auth parameters for specific portal group.

Kernel side support was added earlier at r278161.

Sponsored by: iXsystems, Inc.

MFC r275864: Make sequence numbers checks more strict.

While we don't support MCS, hole in received sequence numbers may mean
only PDU loss. While we don't support lost PDU recovery, terminate the
connection to avoid stuck commands.

While there, improve handling of sequence numbers wrap after 2^32 PDUs.

MFC r273813:

Add discovery-filter. This makes it possible to restrict which targets
are returned during discovery based on initiator portal, name, and CHAP
credentials.

MFC r273543:

Clean up (refactor) discovery a little; no functional changes.

Sponsored by: The FreeBSD Foundation

MFC r270279:

Make the iSCSI stack use __FBSDID() properly.

Sponsored by: The FreeBSD Foundation

MFC r267606:
On discovery stage add set of TargetAddress keys to reply, reporting to
the client all the portal groups addresses and ports.

MFC r261752:

Empty data segment during Login Phase is rather unlikely, but it's
not, by itself, a protocol error. This fixes interoperability with
OpenBSD initiator.

Sponsored by: The FreeBSD Foundation

MFC r261757:

Rename a variable, no functional changes.

Sponsored by: The FreeBSD Foundation

MFC r281532 (by delphij): Eliminate unused headers.

MFC r279589: Fix handling of queued text and logout requests.

While it may have little sense, text and logout requests can be queued.
If they are, they consume cmdsn, so we should increment our conn_cmdsn.

MFC r278322: Add support for multiple portal groups per target.

This change allows multiple "portal-group" options to be specified per
target. Each of them may include new optional auth-group name parameter
to override per-target auth parameters for specific portal group.

Kernel side support was added earlier at r278161.

Sponsored by: iXsystems, Inc.

MFC r275864: Make sequence numbers checks more strict.

While we don't support MCS, hole in received sequence numbers may mean
only PDU loss. While we don't support lost PDU recovery, terminate the
connection to avoid stuck commands.

While there, improve handling of sequence numbers wrap after 2^32 PDUs.

MFC r273813:

Add discovery-filter. This makes it possible to restrict which targets
are returned during discovery based on initiator portal, name, and CHAP
credentials.

MFC r273543:

Clean up (refactor) discovery a little; no functional changes.

Sponsored by: The FreeBSD Foundation

MFC r270279:

Make the iSCSI stack use __FBSDID() properly.

Sponsored by: The FreeBSD Foundation

MFC r267606:
On discovery stage add set of TargetAddress keys to reply, reporting to
the client all the portal groups addresses and ports.

MFC r261752:

Empty data segment during Login Phase is rather unlikely, but it's
not, by itself, a protocol error. This fixes interoperability with
OpenBSD initiator.

Sponsored by: The FreeBSD Foundation

MFC r261757:

Rename a variable, no functional changes.

Sponsored by: The FreeBSD Foundation