MFC 0f34c80f376345b98a972940dd4757e58d7beb06:

Replace the redundant MENTAT macro with SOLARIS.

MENTAT and SOLARIS are synonymous. Remove the extraneous duplicate
macro.

(cherry picked from commit 0f34c80f376345b98a972940dd4757e58d7beb06)

Git Hash: 8d6da0aae1c4ca288537c9875eaed1f65988e51f
Git Author: cy@FreeBSD.org

MFC 4cd1807c7d2a67b633dd0c0bfde15091543a2514:

Retire the K&R/STD C __P prototype declarations.

In the old days when K&R C and STD C were each in use a workaround
(read hack) was required to allow the same code to work on each
without modification. All C compilers support STD C. We can finally
put the __P prototype to rest.

(cherry picked from commit 4cd1807c7d2a67b633dd0c0bfde15091543a2514)

Git Hash: 0c7a33852aa5cd28a9d9b19b8f8034d60a9cb50f
Git Author: cy@FreeBSD.org

MFC r343701 & r343732:

ipfilter #ifdef cleanup.

Remove #ifdefs for ancient and irrelevant operating systems from
ipfilter.

When ipfilter was written the UNIX and UNIX-like systems in use
were diverse and plentiful. IRIX, Tru64 (OSF/1) don't exist any
more. OpenBSD removed ipfilter shortly after the first time the
ipfilter license terms changed in the early 2000's. ipfilter on AIX,
HP/UX, and Linux never really caught on. Removal of code for operating
systems that ipfilter will never run on again will simplify the code
making it easier to fix bugs, complete partially implemented features,
and extend ipfilter.

Unsupported previous version FreeBSD code and some older NetBSD code
has also been removed.

What remains is supported FreeBSD, NetBSD, and illumos. FreeBSD and
NetBSD have collaborated exchanging patches, while illumos has expressed
willingness to have their ipfilter updated to 5.1.2, provided their
zone-specific updates to their ipfilter are merged (which are of interest
to FreeBSD to allow control of ipfilters in jails from the global zone).

Reviewed by: glebius@
Differential Revision: https://reviews.freebsd.org/D19006

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

Update ipfilter 4.1.28 --> 5.1.2.

Approved by: glebius (mentor)
BSD Licensed by: Darren Reed <darrenr@reed.wattle.id.au> (author)

This commit was generated by cvs2svn to compensate for changes in r170263,
which included commits to RCS files with non-trunk default branches.

Import IPFilter 4.1.23 to vendor branch.
See src/contrib/ipfilter/HISTORY for details of changes since 4.1.13

Import IP Filter version 4.1.10

import ipfilter 4.1.8 into the kernel source tree