sstate-diff-machines.sh: Return non-zero return code when there was some failure detected
* add --analyze option, which is useful when using from jenkins job
where you don't want to read output just to dectect how bad it was
* I was always using something like this inside jenkins job, but better
to share it in original script
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
