If user wants to add an extra volumeMounts/volume to a pod,
amd uses override values e.g. like this
pod:
mounts:
nova_placement:
init_container: null
nova_placement:
volumeMounts:
- name: nova-etc
...
helm template parser complains with
Warning: The destination item 'nova_placement' is a table and ignoring the source 'nova_placement' as it has a non-table value of: <nil>
So when we create empty values for such keys in values.yaml, the source
will be present and warning does not need to be shown.
Change-Id: Ib8dc53c3a54e12014025de8fafe16fbe9721c0da
a2a5dda47c