Static layout: Implement PNOR code update

Implement the PNOR code update by pflash tool in openpower-pnor-update
service, and update the related associations.

Tested: Verify PNOR code update succeeds.

Change-Id: I53781d6420071200ac2ed6837f7a79bf5e1162c2
Signed-off-by: Lei YU <mine260309@gmail.com>
diff --git a/static/item_updater_static.hpp b/static/item_updater_static.hpp
index dd7245f..75afeda 100644
--- a/static/item_updater_static.hpp
+++ b/static/item_updater_static.hpp
@@ -35,6 +35,8 @@
 
     void freeSpace() override;
 
+    void updateFunctionalAssociation(const std::string& versionId) override;
+
     bool isVersionFunctional(const std::string& versionId) override;
 
   private:
@@ -61,6 +63,9 @@
     /** @brief Host factory reset - clears PNOR partitions for each
      * Activation D-Bus object */
     void reset() override;
+
+    /** @brief The functional version ID */
+    std::string functionalVersionId;
 };
 
 } // namespace updater