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

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

Begin all license/copyright comments with /*-

Use __FBSDID().

Brought to you by: a boring talk at Ottawa Linux Symposium

In in_cksumdata, len must be a signed type.

Ansify and fix warnings.

This is the first snapshot of the FreeBSD/ia64 kernel. This kernel will
not work on any real hardware (or fully work on any simulator). Much more
needs to happen before this is actually functional but its nice to see
the FreeBSD copyright message appear in the ia64 simulator.