Fix parsing of OCI images
Fix parsing of OCI images

The code apparently intended to use the OCI data to generate
a v2s2 config, instead it only generates the v2s2 config
if OCI parsing fails (from the results of the failed parsing).

Signed-off-by: Miloslav Trmač <mitr@redhat.com>

Closes: #776
Approved by: rhatdan

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