Chassis: Check for standby voltage regulator fault

When an unexpected power down is detected check the standby voltage
regulator fault gpio for a latched fault event. If a regulator fault was
detected then log the event.

Signed-off-by: Ben Tyner <ben.tyner@ibm.com>
Change-Id: I98729118332c7a7785f9048f6ac7cfe1ce882bb6
diff --git a/chassis_state_manager.hpp b/chassis_state_manager.hpp
index 6518ea0..422de59 100644
--- a/chassis_state_manager.hpp
+++ b/chassis_state_manager.hpp
@@ -192,6 +192,15 @@
 
     /** @brief Timer used for tracking power on hours */
     sdeventplus::utility::Timer<sdeventplus::ClockId::Monotonic> pohTimer;
+
+    /** @brief Function to check for a standby voltage regulator fault
+     *
+     *  Determine if a standby voltage regulator fault was detected and
+     *  return true or false accordingly.
+     *
+     *  @return true if fault detected, else false
+     */
+    bool standbyVoltageRegulatorFault();
 };
 
 } // namespace manager