Listener: Register callback API stub

This commit implements a stub API in Listener class to register callback
for all interfaces in correlated_properties.json. This commit also
implements a stub callback API which will be triggered whenever a
property change signal is detected.

Change-Id: Ifdaa2310b397ae9616d921ba2ee657f61dce753e
Signed-off-by: Souvik Roy <souvikroyofficial10@gmail.com>
diff --git a/vpd-manager/oem-handler/ibm_handler.cpp b/vpd-manager/oem-handler/ibm_handler.cpp
index 45e8759..60b0ee8 100644
--- a/vpd-manager/oem-handler/ibm_handler.cpp
+++ b/vpd-manager/oem-handler/ibm_handler.cpp
@@ -171,6 +171,11 @@
             {
                 m_backupAndRestoreObj->backupAndRestore();
             }
+
+            if (m_eventListener)
+            {
+                m_eventListener->registerCorrPropCallBack();
+            }
         }
         else
         {