[oadp-1.6] Update download server to serve raw binaries and drop ppc64le/s390x#175

Joeavaikath merged 2 commits intomigtools:oadp-1.6migtools/oadp-cli:oadp-1.6from

openshift-cherrypick-robot:cherry-pick-174-to-oadp-1.6openshift-cherrypick-robot/oadp-cli:cherry-pick-174-to-oadp-1.6Copy head branch name to clipboard