voltctl log level list does not display the component open-flow-agent

We've noticed that in voltha 2.11 the open-flow-agent component is missing in the voltctl log level list output, as follows:

$ voltctl log level list

COMPONENTNAME PACKAGENAME LEVEL
adapter-open-onu default WARN
global default WARN
read-write-core default WARN
adapter-open-olt default WARN

Our investigation shows that the kv_store_data_prefix entry is missing in the following helm charts:

• voltha-stack/values.yaml
• voltha/templates/ofagent-deploy.yaml
• voltha/values.yaml