code: func legacyPluginMap(opts *ServeOpts) map[string]plugin.Plugin {
  	return map[string]plugin.Plugin{
  		"provider": &ResourceProviderPlugin{
  			ResourceProvider: opts.ProviderFunc,
  		},
  		"provisioner": &ResourceProvisionerPlugin{
  			ResourceProvisioner: opts.ProvisionerFunc,
  		},
  	}
  }
docs: // pluginMap returns the legacy map[string]plugin.Plugin to use for configuring
  // a plugin server or client.