The check-patch-files script checks that all patch files in the
given directory are annotated with an 'Upstream-Status', and
that all patch files are at least noted in their top-level
directory (so we can assume they are used).
In case a violation is detected, it returns a non-zero exit code,
so that a travis-ci reports a violation as build failure.
The bitbake call before each build of a recipe was not required.
Commented out the fresh build, as it currently does not show more
problems than simply building in a shared environment.
Avoiding a fresh environment for each build decreases the runtime
of the test dramatically.
In the previous commit, I accidently also edited another line than intended and
missed to see the accident before committing.
This commit reverts that accident.
Signed-off-by: Lukas Bulwahn <lukas.bulwahn@oss.bmw-carit.de>