osm-deployment: parametrize osm log level in values.yaml (#2046)

* osm-deployment: parametrize log level.

Currently it's hardcoded in deployment. This gives at least some
short term flexibility till we add configMap update, which has some
ongoing discussion as how to tackle.

* address comments

charts/osm/templates/osm-deployment.yaml

@@ -28,7 +28,7 @@ spec:
               containerPort: 15128
           command: ['/osm-controller']
           args: [
-            "--verbosity", "trace",
+            "--verbosity", "{{.Values.OpenServiceMesh.controllerLogLevel}}",
             "--osm-namespace", "{{.Release.Namespace}}",
             "--mesh-name", "{{.Values.OpenServiceMesh.meshName}}",
             "--init-container-image", "{{.Values.OpenServiceMesh.image.registry}}/init:{{ .Values.OpenServiceMesh.image.tag }}",

charts/osm/values.yaml

@@ -43,6 +43,7 @@ OpenServiceMesh:
   meshName: osm
   useHTTPSIngress: false
   envoyLogLevel: error
+  controllerLogLevel: trace
   enforceSingleMesh: false
 
   # Set deployJaeger to true to deploy a Jaeger cluster in the