Mark test as unsupported on C++98/03, since it uses move_iterator

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@316917 91177308-0d34-0410-b5e6-96231b3b80d8

test/std/algorithms/alg.sorting/alg.set.operations/set.union/set_union_move.pass.cpp

@@ -19,6 +19,8 @@
 //   set_union(InIter1 first1, InIter1 last1, InIter2 first2, InIter2 last2,
 //             OutIter result, Compare comp);
 
+// UNSUPPORTED: c++98, c++03
+
 #include <algorithm>
 #include <cassert>
 #include <iterator>