MFC r322773-r322775:
Fix an off-by-two in the llquantize() action parameter validation.

Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

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

Import the dtrace llquantize test files from the vendor area.

Now that we have an illumos vendor area, import the llquantize
test files directly from there to make it easier to track the
code provenance.

Special thanks to Martin Matuska for populating the illumos
vendor area.

Requested by: obrien

Update illumos/dist to revision 13742:b6bbdd77139c
ZFS bits will follow in a separate commit