Prepare DD4hep for Geant4 units in TGeo; Start digitization package

DDDigi/CMakeLists.txt

@@ -19,10 +19,12 @@ dd4hep_add_package_library(DDDigi SOURCES src/*.cpp
   [OPTIONAL TBB REQUIRED]
   )
 if( TBB_INCLUDE_DIR )
-  message( STATUS "TBB_INCLUDE_DIR -->  ${TBB_INCLUDE_DIR}")
-  message( STATUS "TBB_LIBRARY     -->  ${TBB_LIBRARY}")
+  dd4hep_print( "++> TBB_INCLUDE_DIR -->  ${TBB_INCLUDE_DIR}")
+  dd4hep_print( "++> TBB_LIBRARY     -->  ${TBB_LIBRARY}")
   target_compile_definitions(DDDigi PUBLIC DD4HEP_USE_TBB)
   target_link_libraries(DDDigi ${TBB_LIBRARY})
+else()
+  dd4hep_print( "++> TBB_INCLUDE_DIR -->  ${TBB_INCLUDE_DIR}")
 endif()
 
 #---------------------------  Legacy libraries -------------------------------------