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 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 r262907 from ^/projects/release-embedded:
Add ZEDBOARD support for release builds.

Sponsored by: The FreeBSD Foundation

Add ZEDBOARD.

Tested against: stable/10@r262905 (build only)
Sponsored by: The FreeBSD Foundation