avoid using json_object_foreach to allow builds with older libjansson

Author: Hans Zandbelt

src/metadata.c

@@ -656,8 +656,13 @@ static apr_byte_t oidc_metadata_client_register(request_rec *r, oidc_cfg *cfg,
 
 				const char *key;
 				json_t *value;
-				json_object_foreach(json, key, value) {
+
+				void *iter = json_object_iter(json);
+				while(iter) {
+					key = json_object_iter_key(iter);
+					value = json_object_iter_value(iter);
 					json_object_set(data, key, value);
+					iter = json_object_iter_next(json, iter);
 				}
 
 			}