Compare - remove dead compare_set_base, {compare,drift}_matches
Compare - remove dead compare_set_base, {compare,drift}_matches

`compare_matches` is only called from `compare_set_base`.

`compare_set_base` and `drift_matches` are never called.

`@base` is no longer useful, since `compare_set_base` is the only method to save something useful there

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