Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

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

MFC r270279:

Make the iSCSI stack use __FBSDID() properly.

Sponsored by: The FreeBSD Foundation

MFC r264549:

Make it possible for the initiator side to operate in both proxy
and normal mode; this makes it possible to compile with the former
by default, but use it only when neccessary. That's especially
important for the userland part.

Sponsored by: The FreeBSD Foundation

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

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

Bring in the new iSCSI target and initiator.

Reviewed by: ken (parts)
Approved by: re (delphij)
Sponsored by: FreeBSD Foundation