Stop OraParam walker from recursing into scalar fields

Follow-up to eb51c8e: after introducing WALK(), a few call sites
still passed non-Node scalar members (extname, jointype, ctename)
through the walker interface. Those are not parse-tree nodes and should
not participate in recursive traversal.

Drop those WALK() calls so recursion only follows real Node/List
subtrees while preserving the OraParam numbering behavior for object and
query structure fields.

Author: c2main

src/backend/parser/parse_param.c

@@ -1051,8 +1051,6 @@ raw_calculate_oraparamnumbers_walker(Node *node,
 		{
 			 AlterExtensionContentsStmt *stmt = (AlterExtensionContentsStmt *)node;
 
-			 if (WALK(stmt->extname))
-				 return true;
 			 if (WALK(stmt->object))
 				 return true;
 		}
@@ -1570,16 +1568,12 @@ raw_calculate_oraparamnumbers_walker(Node *node,
 				return true;
 			if (WALK(stmt->subquery))
 				return true;
-			if (WALK(stmt->jointype))
-				return true;
 			if (WALK(stmt->joinaliasvars))
 				return true;
 			if (WALK(stmt->functions))
 				return true;
 			if (WALK(stmt->values_lists))
 				return true;
-			if (WALK(stmt->ctename))
-				return true;
 			if (WALK(stmt->coltypes))
 				return true;
 			if (WALK(stmt->coltypmods))