Disable OpenXR runtime on macOS and remove stub module

CMakeLists.txt

@@ -87,24 +87,6 @@ if(${EXTENSION_NAME}_SUPERBUILD)
   return()
 endif()
 
-#-----------------------------------------------------------------------------
-# Virtual Reality is not supported on macOS, create an extension that contains a stub module
-# that just displays the message that Virtual Reality is not supported.
-# This avoids having a build error on the extension build dashboard.
-if(APPLE)
-  add_subdirectory(VirtualRealityStub)
-
-  include(${Slicer_EXTENSION_GENERATE_CONFIG})
-
-  set(EXTENSION_CPACK_INSTALL_CMAKE_PROJECTS)
-  set(${EXTENSION_NAME}_CPACK_INSTALL_CMAKE_PROJECTS "${EXTENSION_CPACK_INSTALL_CMAKE_PROJECTS}" CACHE STRING "List of external projects to install" FORCE)
-
-  list(APPEND CPACK_INSTALL_CMAKE_PROJECTS "${CMAKE_BINARY_DIR};${EXTENSION_NAME};ALL;/")
-  list(APPEND CPACK_INSTALL_CMAKE_PROJECTS "${${EXTENSION_NAME}_CPACK_INSTALL_CMAKE_PROJECTS}")
-  include(${Slicer_EXTENSION_CPACK})
-  return()
-endif()
-
 #-----------------------------------------------------------------------------
 # Extension modules
 add_subdirectory(VirtualReality)