[CMake] Make CPack usable from all dune modules.

CMakeLists.txt

@@ -28,4 +28,3 @@ add_subdirectory("cmake/scripts")
 
 # finalize the dune project, e.g. generating config.h etc.
 finalize_dune_project()
-include(CPack)

cmake/modules/DuneMacros.cmake

@@ -640,6 +640,8 @@ macro(finalize_dune_project)
 
   test_dep()
 
+  include(CPack)
+
   include(FeatureSummary)
   feature_summary(WHAT ALL)
 endmacro(finalize_dune_project)