[OPENMP]Use standard parsing for 'match' clause, NFC.

Reused standard clauses parsing scheme for parsing/matching 'match'
clause in 'declare variant' directive.

llvm-svn: 372635
diff --git a/clang/lib/AST/OpenMPClause.cpp b/clang/lib/AST/OpenMPClause.cpp
index 0312fe6..bfe272b 100644
--- a/clang/lib/AST/OpenMPClause.cpp
+++ b/clang/lib/AST/OpenMPClause.cpp
@@ -44,6 +44,7 @@
   case OMPC_threadprivate:
   case OMPC_uniform:
   case OMPC_device_type:
+  case OMPC_match:
   case OMPC_unknown:
     break;
   }
@@ -129,6 +130,7 @@
   case OMPC_dynamic_allocators:
   case OMPC_atomic_default_mem_order:
   case OMPC_device_type:
+  case OMPC_match:
     break;
   }
 
@@ -206,6 +208,7 @@
   case OMPC_dynamic_allocators:
   case OMPC_atomic_default_mem_order:
   case OMPC_device_type:
+  case OMPC_match:
     break;
   }