This commit adjusts the defaults for the tiered data roles so that they
are enabled by default, or if the node has the legacy data role. This
ensures that the default experience is that the tiered data roles are
enabled.
To fully specifiy the behavior for the tiered data roles then:
- starting a new node with the defaults: enabled
- starting a new node with node.roles configured: enabled if and only
if the tiered data roles are explicitly configured, independently
of the node having the data role
- starting a new node with node.data enabled: enabled unless the
tiered data roles are explicitly disabled
- starting a new node with node.data disabled: disabled unless the
tiered data roles are explicitly enabled