For postmortem analysis it's helpful to know if the build environment was
clean or contained any modifications.
(From OE-Core rev: edaaa2ad311663beabd2416037de00d82fca5fba)
Signed-off-by: Jörg Sommer <joerg.sommer@navimatix.de>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>