Use host state object to check if host is on

The code was using pgood to determine if host is on or off. Now we have
host state object, which is a more appropriate way to check host on/off.
So change pgood related code to use host state object.

Change-Id: I553c1a40922ca2e8bc6904688c55e85971bd4720
Signed-off-by: Lei YU <mine260309@gmail.com>
diff --git a/settings.hpp b/settings.hpp
index db1e5e4..95d20dc 100644
--- a/settings.hpp
+++ b/settings.hpp
@@ -13,6 +13,7 @@
 constexpr auto root = "/";
 constexpr auto timeOwnerIntf = "xyz.openbmc_project.Time.Owner";
 constexpr auto timeSyncIntf = "xyz.openbmc_project.Time.Synchronization";
+constexpr auto hostStateIntf = "xyz.openbmc_project.State.Host";
 
 /** @class Objects
  *  @brief Fetch paths of settings D-bus objects of interest upon construction
@@ -47,6 +48,9 @@
 
         /** @brief time sync method settings object */
         Path timeSyncMethod;
+
+        /** @brief host state object */
+        Path hostState;
 };
 
 } // namespace settings