Move metadata handle name function upstream to podio

Where it belongs

Author: tmadlener

k4FWCore/include/k4FWCore/MetaDataHandle.h

@@ -11,14 +11,6 @@
 
 #include <type_traits>
 
-namespace k4FWCore {
-
-  static std::string metaDataHandleDescriptor(const std::string& collectionName, const std::string& key) {
-    return collectionName + "__" + key;
-  }
-
-}  // namespace k4FWCore
-
 template <typename T> class MetaDataHandle {
 public:
   MetaDataHandle();