Incomplete documentation for read.legacyReadTarget and read.persistence

[peske]

Is your feature request related to a problem? Please describe.
After installing grafana/loki chart in SSD mode, I've noticed that read node doesn't create/use PVCs. After analyzing the source code of the chart, I've concluded that read.persistence is used only if read.legacyReadTarget is set to true. The problem is that this isn't mentioned in the values file, and took me time to prepare unnecessary PVs.

Describe the solution you'd like
Just put line like following before read.persistence:

# Used only if legacyReadTarget is set to true

Describe alternatives you've considered
None

Additional context
Related to grafana/loki chart.

[duj4]

It is mentioned at https://github.com/grafana/loki/blob/main/production/helm/loki/values.yaml#L1539