FreeBSD_HEAD_amd64_gcc - Build #1603 - Fixed

FreeBSD_HEAD_amd64_gcc - Build #1603 - Fixed:

Build information: https://jenkins.FreeBSD.org/job/FreeBSD_HEAD_amd64_gcc/1603/
Full change log: https://jenkins.FreeBSD.org/job/FreeBSD_HEAD_amd64_gcc/1603/changes
Full build log: https://jenkins.FreeBSD.org/job/FreeBSD_HEAD_amd64_gcc/1603/console

Change summaries:

306109 by ache:
1) For already non-standard %z extension implement GNU compatible formats:
+hh and -hh.
2) Check for incorrect values for %z.

MFC after:      7 days

306104 by kib:
Hopefully, fix build of the module outside the kernel tree.

Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks

306102 by kevlo:
Add support for the TP-Link TG-3468 v2.

This is an RTL8168 chip, which we already support so all we have to do is add
the vendor ID.

PR:	212876
Submitted by:	Tobias Kortkamp <t_at_tobik.me>
MFC after:	3 days

306100 by ed:
Refine the dirname(3) compatibility workaround a bit more.

Right now our workaround is so good that it doesn't throw any warnings
on misuse. This means that people will keep on using the old version
of dirname(3) silently without fixing their code.

Go ahead and change the prototype of __old_dirname() to also use a plain
char *, so that we still get a compiler warning. This won't have any
negative effect on building older versions of FreeBSD on HEAD, as those
are built with -Werror disabled.

Differential Revision:	https://reviews.freebsd.org/D7844

306099 by ed:
Fix misuse of the basename() and dirname() functions.

These functions are allowed to overwrite their input. Pull a copy of the
input parameter and call dirname() and basename() on that instead. Do
ensure that we reload the pathname value between calls.