Extend CPPFLAGS, don't replace it

Remove no longer used -DNFS.

Convert mount_nfs to the mount_foo_parseargs() format. No functional
change.

branches: 1.21.12;
Add new Makefile knob, USE_FORT, which extends USE_SSP by turning on the
FORTIFY_SOURCE feature of libssp, thus checking the size of arguments to
various string and memory copy and set functions (as well as a few system
calls and other miscellany) where known at function entry. RedHat has
evidently built all "core system packages" with this option for some time.

This option should be used at the top of Makefiles (or Makefile.inc where
this is used for subdirectories) but after any setting of LIB.

This is only useful for userland code, and cannot be used in libc or in
any code which includes the libc internals, because it overrides certain
libc functions with macros. Some effort has been made to make USE_FORT=yes
work correctly for a full-system build by having the bsd.sys.mk logic
disable the feature where it should not be used (libc, libssp iteself,
the kernel) but no attempt has been made to build the entire system with
USE_FORT and doing so will doubtless expose numerous bugs and misfeatures.

Adjust the system build so that all programs and libraries that are setuid,
directly handle network data (including serial comm data), perform
authentication, or appear likely to have (or have a history of having)
data-driven bugs (e.g. file(1)) are built with USE_FORT=yes by default,
with the exception of libc, which cannot use USE_FORT and thus uses
only USE_SSP by default. Tested on i386 with no ill results; USE_FORT=no
per-directory or in a system build will disable if desired.

Remove Kerberos4/NFSKERB settings.

whitespace.

Use the rpc code from sys/lib/libsa to determine the root file handle.
Saves the code from depending on the xdr functions.
Tested on i386 and IPv4, may need tweaking for IPv6 and using TCP for the
portmap/mount functions.

Move WARNS=3 to the Makefile.inc, and add a little const to the remaining
programs that did not compile before.

Split getnfsargs() out into its own file, it drags in 70kB of rpc code.
I might manage to write a version that doesn't pull in all the crud.
(Which will give a load of space in the install floppy images)

Only compile in IPv6 support if ${USE_INET6} != "no"

MKINET6 is for providing IPv6 infrastructure.
USE_INET6 is for compiling IPv6 support into the programs (needs MKINET6).

PR/1472: David Carrel: Add option to specify the nfs port.
This was not done, I added the functionality to be able to parse
port=num in the options. While I was there, I added this for all
the other numeric options: rsize, wsize etc.

move getmntopts(3) to libutil, build and install also it's manpage
bump libutil minor
adjust individual mount_*/Makefile to use libutil getmntopts(3)

MNT_GETARGS support

Use ${NETBSDSRCDIR}/some/path instead of ${.CURDIR}/../../some/path

CFLAGS->CPPFLAGS

back to using mount/getmntopts.c since mount is now post lite-2

Back out the .PATH.c changes. The .depend problem (and others)
will be fixed using the new .NOPATH make feature instead.

Use .PATH.c: ...

it's a shame, but since we have no kernel support for kerb NFS (which may or may not be worth having, in the form available to us) this is how I'm closing PR #2469.

Bring in NFSv3 code by Rick Macklem (from Lite2).

convert to new RCS Id conventions; reduce my headache

specify man pages the new way.

If in a kerberos environment; build -DKERBEROS

branches: 1.1.1; 1.1.2;
Update from 4.4-Lite, with local changes.