[Flang][OpenMP] Fix MSVC missing include caused by llvm#147442

Windows/MSVC build bots are having issues with a missing header where
linux is not. So, attempt to fix by adding missing header explicitly to file.

Author: agozillon

flang/lib/Lower/OpenMP/DataSharingProcessor.cpp

@@ -26,6 +26,7 @@
 #include "flang/Optimizer/HLFIR/HLFIROps.h"
 #include "flang/Parser/openmp-utils.h"
 #include "flang/Semantics/attr.h"
+#include "flang/Semantics/openmp-directive-sets.h"
 #include "flang/Semantics/tools.h"
 #include "llvm/ADT/Sequence.h"
 #include "llvm/ADT/SmallSet.h"