docs: improve Doxygen comments.

refs: #1435

Change-Id: I21624ef4eec393c82a50229a07e8277fb6ae4ddf
diff --git a/src/route/nexthop-list.cpp b/src/route/nexthop-list.cpp
index dc11113..ed46b55 100644
--- a/src/route/nexthop-list.cpp
+++ b/src/route/nexthop-list.cpp
@@ -59,7 +59,7 @@
   }
 }
 
-/**
+/*!
 Add next hop to the Next Hop list
 If next hop is new it is added
 If next hop already exists in next
@@ -82,7 +82,7 @@
   }
 }
 
-/**
+/*!
 Remove a next hop only if both next hop face and route cost are same
 
 */