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

o Remove EoL whitespaces.

o usage() updated for -h and -X flags.

tools: minor spelling fixes.

Mostly comments but also some user-visible strings.

MFC after: 2 weeks

Create /usr/local/etc before filling things into it.

Only run mtree if the NANO_CUST_FILES_MTREE is nonempty

Also umount the packages on non-signal failure

Add optional configuration knob NANO_CUST_FILES_MTREE. If set, it will
require an entry in custom mtree definition for every custom installed file.

Obtained from: Netflix

Update cust_pkgng with a simpler, more robust version. We don't need
to loop for pkg, which simplifies things.

Add early_customize_cmd() that allows to register custom functions run
before the build stage.

Reviewed by: imp
Obtained from: Netflix

Unquote NANO_PACKAGE_LIST so that it actually can be a list and so
that the default value of "*" works.

Use NANO_LOG instead of NANO_OBJ for log file locations. Have it
default to NANO_OBJ.

Two new variables: NANO_ROOT and NANO_ALTROOT. These used to be
spelled ${NANO_SLICE_ROOT}a and ${NANO_SLICE_ALTROOT}a respectively,
and that's the default value. This will allow nanobsd on systems
without a bsd label. That's rarely needed these days, even in an MBR
world. The default will shift to this in the future, but remain an
option.

Default NANO_DRIVE to ada0 not ad0. This shouldn't affect working
configs (since they'd have to change NANO_DRIVE to be ada0 to work),
but will fix old ones that used to work.

MFC After: 1 week

Make sure that the /set directive gets put at the top of the file,
instead of in sort order. Slash sorts after period.

Eliminate a typo that crept into a last minute change before commit :(

Noticed by: Olivier Cochard-Labbe

Make sure to quote the arg after -n and -z tests.

Fix up mtree with additional entries written to it by
nanobsd. implement support for NanoBSD touching a file (and possibly
recording that fact) as well as replacing a directory with a symlink.
Also specify the default uname and gname for files and use that as a
/set command at the top of the generated METALOG file.

Disable /entropy by default. /var/db/entropy should be enough.
# This eliminates the warning message at boot, but more work may be
# needed.

Generally use shorter, more idiomatic sh expressions in a bunch of
places.

Default serial connection to 115200. Hardly anybody uses slower these
days, and those that do can use NANO_BOOT2CFG to change it.

When building no-priv, chmod etc/defaults/rc.conf before appending to
it and then chmod back. There's no chmod -push / chmod -pop so hard
code 444 as the right permissions here.

Also, fix more stray detritus that crept in (out?) while re-arranging
the deck chairs.

Stupid last minute changes: Add missing } and fi

Pointed out by: Howard Su

Setting NANO_NOPRIV_BUILD will now add -DNO_ROOT and METALOG=xxxx as
appropriate. First step in supporting a build w/o root. More to
follow as actions by customization scripts are not (yet) recorded in
the metalog, and duplicate entries in it aren't removed.

SRCCONF makes no sense in make.conf. Don't set it there. Rely on it
being in the environment. Also filter out the new SRC_ENV_CONF as
well. If you really need these set, set them in your config file,
not in the build environment used to launch nanobsd.

Pointed out by: bdrewery@

Minor cleanup in how we run make:
o Move SRCCONF and __MAKE_CONF into the environment to cope with
file paths with spaces in them better.
o Move the rest of the variable setting command line args into
__MAKE_CONF files.
o Trace the commands that we're using to build so they appear at the
top of the log.
o Be more consistent about quoting paths for cd and similar commands
to better cope with paths with spaces in them, though some more
work is likely needed.
o Add some comments about all this.
o Minor formatting tweaks in a couple places

Sponsored by: Netflix, Inc

Add support for passing TARGET_CPUTYPE into the build. It's more
important for arm and mips than for the more generic x86 systems.

Make the slice names for root configurable. For embedded platforms, we
need s1 to be a FAT partition, s2 to be the config partition and s3
and s4 to be the ping-pong upgrade partitions.

NANO_SLICE_ROOT defaults to s1
NANO_SLICE_ALTROOT defaults to s2
NANO_SLICE_CFG defaults to s3
NANO_SLICE_DATA defaults to s4

All can be overridden in the config file. Some basic sanity checking
is in place, but is no substitute for being careful.

Remove cust_pkg() not that pkg_foo(1) has been removed.

Make NanoBSD source-able from other scripts.

Summary:
This change converts NanoBSD into a two-script bundle.
- defaults.sh contains all non-CLI code. Most NanoBSD code is moved into
this file.
- nanobsd.sh now consists just of a command line interface that calls into
functions in defaults.sh.

Test Plan: Run NanoBSD using a previously-working configuration.

Reviewers: imp

Reviewed By: imp

Differential Revision: https://reviews.freebsd.org/D1321