Update syntax for omitting project UI
Since Aron unkluged my project plugin cmake logic in smtk (smtk!2772 (merged)) we can simplify the superbuild logic for omitting the project UI from those packages that don't use it.
Since Aron unkluged my project plugin cmake logic in smtk (smtk!2772 (merged)) we can simplify the superbuild logic for omitting the project UI from those packages that don't use it.