Fix VC++ compilation error.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25214 91177308-0d34-0410-b5e6-96231b3b80d8

lib/VMCore/TypeSymbolTable.cpp

@@ -15,6 +15,7 @@
 #include "llvm/DerivedTypes.h"
 #include "llvm/ADT/StringExtras.h"
 #include <iostream>
+#include <algorithm>
 
 using namespace llvm;