[stable/telegraf] Allow ENV vars (#15265)

stable/telegraf/Chart.yaml

 apiVersion: v1
 name: telegraf
-version: 1.1.2
+version: 1.1.3
 appVersion: 1.10
 deprecated: false
 description: Telegraf is an agent written in Go for collecting, processing, aggregating, and writing metrics.

stable/telegraf/templates/deployment.yaml

@@ -29,8 +29,7 @@ spec:
         resources:
 {{ toYaml .Values.resources | indent 10 }}
         env:
-        - name: HOSTNAME
-          value: "telegraf-polling-service"
+{{ toYaml .Values.env | indent 8 }}       
         volumeMounts:
         - name: config
           mountPath: /etc/telegraf

stable/telegraf/values.yaml

@@ -11,6 +11,10 @@ image:
 
 podAnnotations: {}
 
+env:
+  - name: HOSTNAME
+    value: "telegraf-polling-service"
+
 ## Configure resource requests and limits
 ## ref: http://kubernetes.io/docs/user-guide/compute-resources/
 resources: {}