feat: Add support for "custom" dataDirs type for volume server in kubernetes helm chart (#6094)

k8s/charts/seaweedfs/values.yaml

@@ -301,6 +301,12 @@ volume:
   #   - name: data
   #     type: "emptyDir"
   #     maxVolumes: 0  # If set to zero on non-windows OS, the limit will be auto configured. (default "7")
+  #
+  # If these don't meet your needs, you can use "custom" here along with extraVolumes and extraVolumeMounts
+  # Particularly useful when using more than 1 for the volume server replicas.
+  #   - name: data
+  #     type: "custom"
+  #     maxVolumes: 0  # If set to zero on non-windows OS, the limit will be auto configured. (default "7")
 
   dataDirs:
   - name: data1
@@ -381,6 +387,15 @@ volume:
   sidecars: []
   initContainers: ""
 
+  # Example for use when using more than 1 volume server replica
+  # extraVolumeMounts: |
+  #   - name: drive
+  #     mountPath: /drive
+  #     subPathExpr: $(POD_NAME)
+  # extraVolumes: |
+  #   - name: drive
+  #     hostPath:
+  #       path: /var/mnt/
   extraVolumes: ""
   extraVolumeMounts: ""