[VOL-3798] : voltha helm chart change to enable/disable metrics for openonu-go

Change-Id: If03b10b07c2afa687415889aed493d973854175a
diff --git a/voltha-adapter-openonu/templates/openonu-go-deploy.yaml b/voltha-adapter-openonu/templates/openonu-go-deploy.yaml
index 500db47..14519f3 100644
--- a/voltha-adapter-openonu/templates/openonu-go-deploy.yaml
+++ b/voltha-adapter-openonu/templates/openonu-go-deploy.yaml
@@ -99,6 +99,7 @@
             - "--trace_enabled={{ .Values.global.tracing.enabled }}"
             - "--trace_agent_address={{ tpl .Values.services.tracing_agent.address . }}"
             - "--allowed_onu_vendors={{ template "allowed_onu_vendors" . }}"
+            - "--metrics_enabled={{ .Values.global.metrics.enabled }}"
           {{- if .Values.securityContext.enabled }}
           securityContext:
             allowPrivilegeEscalation: false