This change introduces two fix about CNIVersion. One is to add CNIVersion into
delegated CNI conflist in case of DEL if CNIVersion is missing. ParseVersion() in libcni
checks cniVersion as mandatory field and sometimes user/daemonset miss it.
The latest flannel daemonset yaml (of flannel github) does not have CNIVersion, for example.
This change adds CNIVersion from multus config if cniVersion is missing (empty) in delegated
CNI config.
In addition, this fix also adds '--cni-version' in entrypoint.sh to add cniVersion in multus
config in case of '--multus-conf-file=auto'.
