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

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

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

Make the variadic macro debug() comply to C99.

Clear devinfo_generation in devinfo_free() since we are freeing all of the
cached state. Otherwise, a subsequent call to devinfo_init() would succeed
without reading the device tree from the kernel thinking that the cached
state was up to date since the generation count was the same. However,
since the cached state was actually free'd, attempts to examine the tree
after the second devinfo_init() would fail.

Reported by: Juho Vuori juho dot vuori at kepa dot fi
Submitted by: Stefan Farfeleder stefan at fafoe dot narf dot at
Approved by: re (dwhite)
MFC after: 1 week

Remove unused variables. Whitespace cleaning.

Fix typo in a comment.

Prefer C99's __func__ over GCC's __FUNCTION__.

Expose the new kernel data structures to libdevinfo:
o Added dd_pnpinfo, dd_location, dd_devflags, dd_flags and dd_state
o Copy/initialize these as necessary.
o Document the changes to the interface in devinfo.3.

Implement __FBSDID()

Include string.h for the strlen() prototype to quiet a warning.

This is the Device Information Library, libdevinfo.

The devinfo library provides access to the kernel's internal device
hierarchy and to the I/O resource manager. The library uses a
sysctl(9) interface to obtain a snapshot of the kernel's state which
is then made available to the application.