make it possible to select supported devices in the operator

[mythi]

There are cases where only the selected devices/their CRDs are wanted/needed in the operator. The operator deployment shall support this by making it possible to:

• add --devices cmdline to operator main.go which defines the controllers/webhooks to set up. refactor main
• do not deploy fpga/sgx mutating pod webhooks' MutatingWebhookConfigurations
• kustomize the unwanted RBAC / CRD settings: add operator/device/xyx kustomize overlay that 1) deploys the CRD for xyz device and patches manager.yaml to add --devices xyz param to manager.
• document per device deployment

[msivosuo]

#599