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

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

style cleanup: Remove duplicate $FreeBSD$ tags.

These files had tags after teh copyright notice,
inside the comment block (incorrect, removed),
and outside the comment block (correct).

Approved by: rwatson (mentor)

Use __FBSDID.

Fix a few more dependancy violations.

Fix a whole bunch of dependancy bugs and make it actually work when the
size is not a multiple of eight.

Fix a couple of dumb mistakes.

Initial libc port for ia64.