Add some <cstdio> includes to unbreak the buildbots

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@98591 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Rewrite/HTMLRewrite.cpp b/lib/Rewrite/HTMLRewrite.cpp
index cf1c779..6fe3fc0 100644
--- a/lib/Rewrite/HTMLRewrite.cpp
+++ b/lib/Rewrite/HTMLRewrite.cpp
@@ -22,6 +22,7 @@
 #include "llvm/ADT/OwningPtr.h"
 #include "llvm/Support/MemoryBuffer.h"
 #include "llvm/Support/raw_ostream.h"
+#include <cstdio>
 using namespace clang;