MFC: r346856
Add #ifdef INET6 around declaration of nbuf.

It was reported that without #ifdef INET6 around the declaration of "nbuf",
a build would report an unused variable. For some reason, I didn't see that
warning when I did a build, but it seems reasonable to add these #ifdef INET6's.

MFC: r346709
Add support to nfsdumpstate for printing of INET6 addresses for locks.

r346190 added support for printing of INET6 addresses for the "-o" option
(all opens) but missed adding support for INET6 addresses for the "-l" option.
This patch adds that support.

MFC: r346190
Fix nfsdumpstate(8) so that it can print out INET6 callback addresses.

The patch adds support for printing of INET6 callback addresses.
It also adds the #ifdef INET, INET6 as requested by bz@.

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

Add META_MODE support.

Off by default, build behaves normally.
WITH_META_MODE we get auto objdir creation, the ability to
start build from anywhere in the tree.

Still need to add real targets under targets/ to build packages.

Differential Revision: D2796
Reviewed by: brooks imp

Fix handling of the "-l" argument for nfsdumpstate(8).

Submitted by: zack.kirsch at isilon.com
MFC after: 2 weeks

mdoc: replace troff macros with -mdoc equivalents

Code cleanup for nfs4 utilities:

- Mark internal routines as static;
- Eliminate unused parameters where possible, mark __unused for others;
- Remove unused variables;
- Use %jd for int64_t values in printf();
- Add appropriate %d for printf to match its parameter;
- Rename a variable to resolve conflict with revoke(2);

Reviewed by: rmacklem
Tested with: make universe (bugs are mine)

Add two new utilities and two new daemons to /usr/src/usr.sbin that
are specifically used by the experimental nfsv4 subsystem.
nfscbd - The NFSv4 client callback daemon.
nfsuserd - The NFSv4 daemon that maps between user and group name
and their corresponding uid/gid numbers.
nfsdumpstate - A utility that dumps out the NFSv4 Open/Lock state.
nfsrevoke - Administratively revokes an NFSv4 client, releasing all
NFSv4 Open/Lock state it holds on the server.

Approved by: kib (mentor)