removed unused 'using' declaration

src/amdis/common/ForEach.hpp

@@ -18,7 +18,6 @@ namespace AMDiS
     template <class Functor, class... Args>
     constexpr void for_variadic(Functor&& f, Args&&... args)
     {
-      using std::get;
 #if AMDIS_HAS_CXX_FOLD_EXPRESSIONS
       (f(FWD(args)),...);
 #else