[OPENMP50]Basic parsing/sema analysis for order(concurrent) clause.

Added parsing/sema/serialization support for order(concurrent) clause in
loop|simd-based directives.
diff --git a/clang/lib/AST/OpenMPClause.cpp b/clang/lib/AST/OpenMPClause.cpp
index 5ef8264..c7e7f33 100644
--- a/clang/lib/AST/OpenMPClause.cpp
+++ b/clang/lib/AST/OpenMPClause.cpp
@@ -137,6 +137,7 @@
   case OMPC_device_type:
   case OMPC_match:
   case OMPC_nontemporal:
+  case OMPC_order:
     break;
   }
 
@@ -216,6 +217,7 @@
   case OMPC_device_type:
   case OMPC_match:
   case OMPC_nontemporal:
+  case OMPC_order:
     break;
   }
 
@@ -1691,3 +1693,8 @@
     OS << ")";
   }
 }
+
+void OMPClausePrinter::VisitOMPOrderClause(OMPOrderClause *Node) {
+  OS << "order(" << getOpenMPSimpleClauseTypeName(OMPC_order, Node->getKind())
+     << ")";
+}