docs: Update documentation and Doxygen documentation generation
diff --git a/utils/ndn-fw-hop-count-tag.h b/utils/ndn-fw-hop-count-tag.h
index 0ed62f0..f530961 100644
--- a/utils/ndn-fw-hop-count-tag.h
+++ b/utils/ndn-fw-hop-count-tag.h
@@ -27,6 +27,7 @@
 namespace ndn {
 
 /**
+ * @ingroup ndn-fw
  * @brief Packet tag that is used to track hop count for Interest-Data pairs
  */
 class FwHopCountTag : public Tag