Add option to disable operator resources in Helm chart

[jiuxia211]

What this PR does / why we need it:

Fixes #1308

Which issue(s) this PR fixes:

Fixes #

Does this PR introduced a user-facing change?

Add option to disable operator resources in Helm chart

Additional documentation, usage docs, etc.:

Now can deploy fluent-operator and fluentbit one after another like this
helm install fluent-operator --create-namespace -n fluent charts/fluent-operator/  --set containerRuntime=containerd --set operator.enable=true --set fluentbit.enable=false
helm install fluentbit --create-namespace -n fluent charts/fluent-operator/  --set containerRuntime=containerd --set operator.enable=false --set fluentbit.enable=true

If operator.enable be set to false, this will disable the creation of ClusterRole, ClusterRoleBinding,Deployment, and ServiceAccount resources