Serialization/GlobalModuleIndex.cpp: Fixup r173405, <cstdio>

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@173408 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Serialization/GlobalModuleIndex.cpp

@@ -26,6 +26,7 @@
 #include "llvm/Support/LockFileManager.h"
 #include "llvm/Support/MemoryBuffer.h"
 #include "llvm/Support/PathV2.h"
+#include <cstdio>
 using namespace clang;
 using namespace serialization;