[OPENMP 5.0]Initial support for 'allocator' clause.

Added parsing/sema analysis/serialization/deserialization for the
'allocator' clause of the 'allocate' directive.

llvm-svn: 355952
diff --git a/clang/lib/AST/DeclPrinter.cpp b/clang/lib/AST/DeclPrinter.cpp
index d023a03..2009673 100644
--- a/clang/lib/AST/DeclPrinter.cpp
+++ b/clang/lib/AST/DeclPrinter.cpp
@@ -1560,6 +1560,12 @@
     }
     Out << ")";
   }
+  if (!D->clauselist_empty()) {
+    Out << " ";
+    OMPClausePrinter Printer(Out, Policy);
+    for (OMPClause *C : D->clauselists())
+      Printer.Visit(C);
+  }
 }
 
 void DeclPrinter::VisitOMPRequiresDecl(OMPRequiresDecl *D) {