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

Add the OpenSolaris lockstat(1M) command. Requires the dtrace driver,
the lockstat provider, and the ksyms(4) pseudo driver kernel modules.

Approved by: gnn (mentor)