Service#get_node_info: remove dead code cleanup.
Service#get_node_info: remove dead code cleanup.

Issues:
  * TreeBuilder.get_model_for_prefix(@nodetype) already tested as
	'Service'
  * Under 'Hash' there are 2 possibilities: 'asrv' and 'rsrv' in
	TreeBuilderServices
  * There's no 'root' node in the :svcs_tree tree.
  * There's only :svcs_tree tree in Service controller
  * There's nothing for the else branch, Service is already handled.

ManageIQ/manageiq-ui-classic,ManageIQ/manageiq-ui-classic,ManageIQ/manageiq-ui-classic,ManageIQ/manageiq-ui-classic