Description:
When use `oc adm release mirror` with option --from-dir will hit error :
error: must specify a release image with --from

How reproducible: Always

Steps:
Use `oc adm release new` to create the release manifests to a directory;
`oc adm release new --reference-mode=source --keep-manifest-list -f 12708358_4.11.0-0.nightly-multi-2022-04-18-120932-release-imagestream.yaml --name 4.11.0-0.nightly --to-dir=/tmp/new4.11releaseimage`
Use `oc adm release mirror` with --from-dir to mirror the image :
`oc adm release mirror --from-dir=/tmp/new4.11releaseimage --keep-manifest-list --to=localhost:5000/psundara/openshift-release --apply-release-image-signature --insecure`

Actual Result:
2. Hit error:
oc adm release mirror --from-dir=/tmp/new4.11releaseimage --keep-manifest-list --to=localhost:5000/psundara/openshift-release --apply-release-image-signature --insecure
error: must specify a release image with --from

Expected Result:
2. Could read the release manifests and mirror the image successfully.