[OPENMP 5.0]Add initial support for 'allocate' directive.

Added parsing/sema analysis/serialization/deserialization support for
'allocate' directive.

llvm-svn: 355614
diff --git a/clang/lib/CodeGen/CGStmtOpenMP.cpp b/clang/lib/CodeGen/CGStmtOpenMP.cpp
index 020f0b2..6827222 100644
--- a/clang/lib/CodeGen/CGStmtOpenMP.cpp
+++ b/clang/lib/CodeGen/CGStmtOpenMP.cpp
@@ -3963,6 +3963,7 @@
   case OMPC_nowait:
   case OMPC_untied:
   case OMPC_threadprivate:
+  case OMPC_allocate:
   case OMPC_depend:
   case OMPC_mergeable:
   case OMPC_device: