Add the method to set Functional property based on Group state

When a particular LED Group asserted property is set to true, then the
functional state of that FRU is false and vice-versa. This commit adds
that behavior. Functional status is defined in
xyz.openbmc_project.State.Decorator.OperationalStatus interface.

Tested: When manually set the Asserted property to true by the D-Bus,
we can see that the Functional is updated to false.

Signed-off-by: George Liu <liuxiwei@inspur.com>
Change-Id: I6fa7a4c41363263d345b6b5335056fad15efb78c
diff --git a/manager.hpp b/manager.hpp
index 390c8fe..91f8b53 100644
--- a/manager.hpp
+++ b/manager.hpp
@@ -105,6 +105,16 @@
      */
     void driveLEDs(group& ledsAssert, group& ledsDeAssert);
 
+    /** @brief Set OperationalStatus according to the status of asserted
+     *         property
+     *
+     *  @param[in]  path          -  D-Bus path of group
+     *  @param[in]  value         -  Could be true or false
+     *
+     *  @return: None
+     */
+    void setOperationalStatus(const std::string& path, bool value) const;
+
   private:
     /** @brief sdbusplus handler */
     sdbusplus::bus::bus& bus;