Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

MFC r271676, r271677, r271678:

r271676:
Catch up with Crochet changes to fix the BEAGLEBONE
build.

r271677:
Catch up with Crochet changes to fix the WANDBOARD-QUAD
build.

r271678:
Set a static revision of the Crochet checkout to avoid
surprise build failures.

Approved by: re (marius)
Sponsored by: The FreeBSD Foundation

MFC r270417, r270418, r270455, r270457:

r270417:
Fix arm build breakage when building stable/10 on
head/.

r270418:
Also export UNAME_r to fix arm builds.

r270455:
Set OSREL and UNAME_r in release/release.sh when building
ports to prevent ports build failures from killing the
release build.

r270457:
Wrap a long line.

Sponsored by: The FreeBSD Foundation

MFC r268232:
The u-boot tarball needed for some boards, BEAGLEBONE for
example, explicitly hard-code gcc(1) as the compiler.

Partially revert r264703, which did a post-chroot install
of gcc(1). This was initially removed because gcc(1) fails
to build usr.bin/dtc/ causing the xdev target to fail. So
this time, move the gcc(1) installation after xdev is built.

This change is likely applicable to stable/10 arm build
failures, as well.

Sponsored by: The FreeBSD Foundation

MFC r264794:
Move xdev knobs from release/arm/release.sh and into an
XDEV_FLAGS variable in ${KERNCONF}.conf file.

Local changes:
Fix XDEV_FLAGS for stable/10 branch, in particular, remove
WITH_GCC_BOOTSTRAP=1 and add WITH_GNUCXX=1.

Sponsored by: The FreeBSD Foundation

MFC r264518, r264697, r264698, r264703:

r264518:
Fix armv6 build failure: "armv6-freebsd-gcc: not found"

r264697:
When building the 'xdev' target when WITH_GCC=1 and
WITHOUT_CLANG_IS_CC=1, it appears WITHOUT_CLANG=1 must
also be set.

While here, reorder the lines to put the WITH_* and
WITHOUT_* entries on the same line.

r264698:
Fix EOL escape.

r264703:
Apply a slightly different color hammer to arm/release.sh:

- gcc(1) fails to build usr.bin/dtc
- lack of WITH_GNUCXX=1 causes cc1plus(1) calls to fail
- u-boot fails to build with clang (hard-coded gcc(1) calls)

Implement the proper incantation of WITH_/WITHOUT_ knobs
to get arm snapshot builds working again.

Since the cc(1) binary no longer needs to be cc(1) instead of
clang(1), remove the chroot(8) post-install cc(1) overwrite.

Sponsored by: The FreeBSD Foundation

MFC r264107:
Remove only-works-on-amd64 restriction.

Sponsored by: The FreeBSD Foundation

MFC r262810, r262862, r264105:
r262810:
Merge enabling building FreeBSD/arm images as part of the
release build process.

r262862:
Provide backwards-compatibility with release.conf SVNROOT
entries that do not have a trailing '/'.

r264105:
Add ZEDBOARD support for release builds.

* Local modifications:
- Set SRCBRANCH from head/ to stable/10/.
- Strip svn:merginfo from ^/projects/release-embedded to avoid
pollution.

Sponsored by: The FreeBSD Foundation

Merge ^/projects/release-embedded into ^/head.

After several months of testing and fixing (and breaking)
various parts of release/release.sh changes, it is now
possible to build FreeBSD/arm images as part of the release
process.

When EMBEDDEDBUILD is set in the release.conf file, release.sh
will create the build environment, then run a separate script
in release/${XDEV}/release.sh [1]. Currently, only arm is
supported.

The release/${XDEV}/release.sh configures the build environment
specific for the target image, such as installing gcc(1),
installing additional third-party software from the ports tree,
and fetching external sources.

Once the build environment is set up, release/${XDEV}/release.sh
runs Crochet, written by Tim Kientzle, which builds the userland
and kernel, and creates an image that can be written to an SD
card with dd(1). Many thanks to Tim for his work on Crochet.

Sample configurations for FreeBSD/arm boards are in the
release/arm/ directory, and Crochet configuration files for each
board are located in release/tools/arm/. Supported boards at this
time are: BEAGLEBONE, PANDABOARD, RPI-B, and WANDBOARD-QUAD.

Adding support for additional boards will continue in the
projects/release-embedded/ branch, and incrementally merged back
to head/.

Many thanks to the FreeBSD Foundation for the support and
sponsorship of this project.

[1] XDEV is used in order to keep the various configurations
organized by architecture, but since TARGET and TARGET_ARCH
are used to build the chroot, the values of those variables
cannot be used.

MFC after: 1 month
Sponsored by: The FreeBSD Foundation

Merge the following:
^/user/gjb/hacking/release-embedded:
259994,260000,260895-260896,261139,261152,
261174,261176,261210,261221,261237,261239,
261448,261489
^/user/gjb/release-embedded:
262305,262307

svn:mergeinfo is intentionally not included in the commit, so it does
not propagate to head/.

Sponsored by: The FreeBSD Foundation

Implement cross build support for embedded devices into
release.sh:

- Modify release/release.sh to recognize an 'EMBEDDEDBUILD'
variable. When set, release/release.sh will build the chroot
userland as is done for big-iron builds.

- Instead of running the 'buildworld', 'buildkernel', and
'release' targets in the chroot, a separate script is run.
The script tools/release/${XDEV}/release.sh sets up the rest
of the chroot workspace, such as installing ports that will
be needed, and building the 'xdev' target.

- crochet (by kientzle@) is checked out from the upstream
repository (and if needed, u-boot, in the case of Raspberry
Pi).

- tools/release/${XDEV}/release.sh then runs crochet with
a configuration file specific to the ${KERNCONF} being built.

Note that this is effectively a first-pass attempt to integrate
this into the release process.

Tested against: head@r259961
Sponsored by: The FreeBSD Foundation