VOL-1797 - fix helm lint issues

Change-Id: I74ccff1f7f431e05fc3963d0707382f478a010f0
diff --git a/voltha/templates/api-server.yaml b/voltha/templates/api-server.yaml
index 0221e60..5b690e6 100644
--- a/voltha/templates/api-server.yaml
+++ b/voltha/templates/api-server.yaml
@@ -51,7 +51,7 @@
       serviceAccountName: {{ .Values.serviceaccount }}
       containers:
       - name: arouter
-        image: {{ tpl .Values.images.afrouter.registry . }}{{ tpl .Values.images.afrouter.repository . }}:{{ tpl .Values.images.afrouter.tag . }}
+        image: {{ tpl .Values.images.afrouter.registry . }}{{ tpl .Values.images.afrouter.repository . }}:{{ tpl ( tpl .Values.images.afrouter.tag . ) . }}
         imagePullPolicy: {{ tpl .Values.images.afrouter.pullPolicy . }}
         volumeMounts:
         - name: config-volume
@@ -71,7 +71,7 @@
           value: {{ mul .Values.replicas.rw_core 2 | quote}}
         - name: NUM_RO_PODS
           value: {{ quote .Values.replicas.ro_core }}
-        image: {{ tpl .Values.images.afrouterd.registry . }}{{ tpl .Values.images.afrouterd.repository . }}:{{ tpl .Values.images.afrouterd.tag . }}
+        image: {{ tpl .Values.images.afrouterd.registry . }}{{ tpl .Values.images.afrouterd.repository . }}:{{ tpl ( tpl .Values.images.afrouterd.tag . ) . }}
         imagePullPolicy: {{ tpl .Values.images.afrouterd.pullPolicy . }}
         command: ["/app/arouterd"]
       restartPolicy: Always
diff --git a/voltha/templates/cli.yaml b/voltha/templates/cli.yaml
index fe5afa5..e185730 100644
--- a/voltha/templates/cli.yaml
+++ b/voltha/templates/cli.yaml
@@ -54,7 +54,7 @@
       serviceAccountName: {{ .Values.serviceaccount }}
       containers:
         - name: vcli
-          image: {{ tpl .Values.images.cli.registry . }}{{ tpl .Values.images.cli.repository . }}:{{ tpl .Values.images.cli.tag . }}
+          image: {{ tpl .Values.images.cli.registry . }}{{ tpl .Values.images.cli.repository . }}:{{ tpl ( tpl .Values.images.cli.tag . ) . }}
           imagePullPolicy: {{ tpl .Values.images.cli.pullPolicy . }}
           env:
             - name: POD_IP
diff --git a/voltha/templates/ofagent.yaml b/voltha/templates/ofagent.yaml
index 81f83ec..6ff7c03 100644
--- a/voltha/templates/ofagent.yaml
+++ b/voltha/templates/ofagent.yaml
@@ -37,7 +37,7 @@
       serviceAccountName: {{ .Values.serviceaccount }}
       containers:
       - name: ofagent
-        image: {{ tpl .Values.images.ofagent.registry . }}{{ tpl .Values.images.ofagent.repository . }}:{{ tpl .Values.images.ofagent.tag . }}
+        image: {{ tpl .Values.images.ofagent.registry . }}{{ tpl .Values.images.ofagent.repository . }}:{{ tpl ( tpl .Values.images.ofagent.tag . ) . }}
         imagePullPolicy: {{ tpl .Values.images.ofagent.pullPolicy . }}
         env:
         - name: CONTROLLER_SERVICE
diff --git a/voltha/templates/ro-core.yaml b/voltha/templates/ro-core.yaml
index b7cbb42..ce4a6bd 100644
--- a/voltha/templates/ro-core.yaml
+++ b/voltha/templates/ro-core.yaml
@@ -51,7 +51,7 @@
       serviceAccountName: {{ .Values.serviceaccount }}
       containers:
         - name: voltha
-          image: {{ tpl .Values.images.ro_core.registry . }}{{ tpl .Values.images.ro_core.repository . }}:{{ tpl .Values.images.ro_core.tag . }}
+          image: {{ tpl .Values.images.ro_core.registry . }}{{ tpl .Values.images.ro_core.repository . }}:{{ tpl ( tpl .Values.images.ro_core.tag . ) . }}
           imagePullPolicy: {{ tpl .Values.images.ro_core.pullPolicy . }}
           env:
             - name: NAMESPACE
diff --git a/voltha/templates/rw-core.yaml b/voltha/templates/rw-core.yaml
index ee2ddd0..28e5f22 100644
--- a/voltha/templates/rw-core.yaml
+++ b/voltha/templates/rw-core.yaml
@@ -14,7 +14,7 @@
 
 {{- $root := . -}}
 {{- $count := mul .Values.replicas.rw_core 2 | int }}
-{{- $tag := tpl .Values.images.rw_core.tag . }}
+{{- $tag := tpl ( tpl .Values.images.rw_core.tag . ) . }}
 {{- $repository := tpl .Values.images.rw_core.repository . }}
 {{- $registry := tpl .Values.images.rw_core.registry . }}
 {{- $pullpolicy := tpl .Values.images.rw_core.pullPolicy . }}