VPD Tool: Fix for silencing unused variable warning

Signed-off-by: PriyangaRamasamy <priyanga24@in.ibm.com>
Change-Id: I05bdf989896a983b435ceefebc482d267a9c57f8
diff --git a/vpd_tool_impl.hpp b/vpd_tool_impl.hpp
index 3062c3b..8757c31 100644
--- a/vpd_tool_impl.hpp
+++ b/vpd_tool_impl.hpp
@@ -117,6 +117,9 @@
      */
     void eraseInventoryPath(std::string& fru);
 
+    /** @brief printReturnCode */
+    void printReturnCode(int returnCode);
+
   public:
     /**
      * @brief Dump the complete inventory in JSON format