MFC r277300 (by smh): Mechanically convert cddl sun #ifdef's to illumos

Since the upstream for cddl code is now illumos not sun, mechanically
convert all sun #ifdef's to illumos #ifdef's which have been used in all
newer code for some time.

Also do a manual pass to correct the use if #ifdef comments as per style(9)
as well as few uses of #if defined(__FreeBSD__) vs #ifndef illumos.

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

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

Commit a patch that fixes a problem in the #pragma statement when searching
for and loading dependent modules. This addresses a bug seen with
io.d where it was being doubly included.

PR: 171678
Submitted by: Mark Johnston
MFC after: 2 weeks

Dtrace: improve handling of library paths.

Merge changes from illumos

906 dtrace depends_on pragma should search all library paths, not just the
current one

949 dtrace should only include the first instance of a library found on
its library path

Illumos Revisions: 13353:936a1e45726c
13354:2b2c36a81512

Reference:
https://www.illumos.org/issues/906
https://www.illumos.org/issues/949

Tested by: Fabian Keil
Obtained from: Illumos
MFC after: 3 weeks

Merge FreeBSD include file changes with some code that should have come
in on the vendor branch.

This commit was generated by cvs2svn to compensate for changes in r178528,
which included commits to RCS files with non-trunk default branches.

Vendor import of the full userland contrib part of DTrace support from
OpenSolaris. This commit resets files to match the versions in the
OpenSolaris tree as of 2008/04/10.

The changes in this import from the previous import are the ones that
will subsequently re-applied to take files off the vendor branch. This
is unfortunately necessary because the Solaris developers won't allow
FreeBSD support #ifdefs in their source code because that creates
'dead code' (stuff that they never compile).

Vendor import of libraries for DTrace from OpenSolaris.