community/polkit: remove dbus-glib-dev and gtk-doc from makedepends
gtk-doc is not used since the gtk_doc option is disabled.
dbus-glib usage has been removed in https://github.com/polkit-org/polkit/commit/f2f2f6db1ef8ea855737cff91d8876365b9b308d
gtk-doc is not used since the gtk_doc option is disabled.
dbus-glib usage has been removed in https://github.com/polkit-org/polkit/commit/f2f2f6db1ef8ea855737cff91d8876365b9b308d