Fix superbuild
Fix superbuild

External-ITKDoxygenXML.cmake has been relocated in the cmake/ folder and this
file has to been updated.

InsightSoftwareConsortium/ITKExamples,InsightSoftwareConsortium/ITKExamples,InsightSoftwareConsortium/ITKExamples,InsightSoftwareConsortium/ITKExamples,InsightSoftwareConsortium/ITKExamples