Don't fallback back immediately to blob upload if the cross-repo mount
fails and layer upload is initiated by registry.
Instead cancel the upload and re-try cross-repo mount from different
source repository before doing full re-upload.
Signed-off-by: Michal Minář <miminar@redhat.com>
Upstream-commit: c6dd51c32cfccc06e77b4f7cb2358f788753df72
Component: engine