add missing vendor/github.com/containers/libpod/vendor.conf
add missing vendor/github.com/containers/libpod/vendor.conf

Signed-off-by: Valentin Rothberg <rothberg@redhat.com>

Closes: #1350
Approved by: TomSweeneyRedHat

rhatdan/buildah,rhatdan/buildah,rhatdan/buildah,nalind/buildah-1,nalind/buildah,TomSweeneyRedHat/buildah,projectatomic/buildah,projectatomic/buildah,projectatomic/buildah,TomSweeneyRedHat/buildah,nalind/buildah-1,nalind/buildah-1,TomSweeneyRedHat/buildah,nalind/buildah