Remove unused AST classes

Author: kparzysz

flang/include/flang/Parser/dump-parse-tree.h

@@ -538,9 +538,6 @@ class ParseTreeDumper {
   NODE_ENUM(OmpCloseModifier, Value)
   NODE(parser, OmpContainsClause)
   NODE(parser, OmpContextSelectorSpecification)
-  NODE(parser, OmpDeclareTargetSpecifier)
-  NODE(parser, OmpDeclareTargetWithClause)
-  NODE(parser, OmpDeclareTargetWithList)
   NODE(parser, OmpDeclareVariantDirective)
   NODE(parser, OmpDefaultClause)
   NODE_ENUM(OmpDefaultClause, DataSharingAttribute)

flang/include/flang/Parser/parse-tree.h

@@ -4943,24 +4943,6 @@ struct OmpDeclareVariantDirective {
   CharBlock source;
 };
 
-// 2.10.6 declare-target -> DECLARE TARGET (extended-list) |
-//                          DECLARE TARGET [declare-target-clause[ [,]
-//                                          declare-target-clause]...]
-struct OmpDeclareTargetWithList {
-  WRAPPER_CLASS_BOILERPLATE(OmpDeclareTargetWithList, OmpObjectList);
-  CharBlock source;
-};
-
-struct OmpDeclareTargetWithClause {
-  WRAPPER_CLASS_BOILERPLATE(OmpDeclareTargetWithClause, OmpClauseList);
-  CharBlock source;
-};
-
-struct OmpDeclareTargetSpecifier {
-  UNION_CLASS_BOILERPLATE(OmpDeclareTargetSpecifier);
-  std::variant<OmpDeclareTargetWithList, OmpDeclareTargetWithClause> u;
-};
-
 // Ref: [4.5:110-113], [5.0:180-185], [5.1:210-216], [5.2:206-207],
 //      [6.0:346-348]
 //

flang/lib/Parser/unparse.cpp

@@ -2492,9 +2492,6 @@ class UnparseVisitor {
   void Unparse(const OpenMPCriticalConstruct &x) {
     Unparse(static_cast<const OmpBlockConstruct &>(x));
   }
-  void Unparse(const OmpDeclareTargetWithList &x) {
-    Put("("), Walk(x.v), Put(")");
-  }
   void Unparse(const OmpInitializerProc &x) {
     Walk(std::get<ProcedureDesignator>(x.t));
     Put("(");