pseq: Add support for UCD90160 device

Refactor power sequencer class hierarchy to add support for the UCD90160
device.

Tested:
* Verify UCD information is obtained successfully from EntityManager
* Verify JSON configuration file is found and parsed successfully
* Test where no pgood error occurs
  * During power on
    * Verify power on continues
    * Verify no error is logged
  * After chassis is powered on
    * Verify chassis remains powered on
    * Verify no error is logged
* Test where pgood error occurs
  * During power on
    * Verify power on stops and chassis is powered off
    * Verify correct error is logged
    * Verify callouts and additional data in error log are correct
    * Detected via rail
    * Detected via pin
  * After chassis is powered on
    * Verify chassis is powered off
    * Verify correct error is logged
    * Verify callouts and additional data in error log are correct
    * Detected via rail
    * Detected via pin

Signed-off-by: Jim Wright <jlwright@us.ibm.com>
Change-Id: Ib00bc1ea34b504c245a4f0cb3979a86e51507f3c
Signed-off-by: Shawn McCarney <shawnmm@us.ibm.com>
diff --git a/phosphor-power-sequencer/src/power_sequencer_monitor.hpp b/phosphor-power-sequencer/src/power_sequencer_monitor.hpp
index ed095bb..740b0cd 100644
--- a/phosphor-power-sequencer/src/power_sequencer_monitor.hpp
+++ b/phosphor-power-sequencer/src/power_sequencer_monitor.hpp
@@ -8,6 +8,10 @@
 namespace phosphor::power::sequencer
 {
 
+constexpr auto powerOnTimeoutError =
+    "xyz.openbmc_project.Power.Error.PowerOnTimeout";
+constexpr auto shutdownError = "xyz.openbmc_project.Power.Error.Shutdown";
+
 /**
  * @class PowerSequencerMonitor
  * Define a base class for monitoring a power sequencer device.
@@ -52,7 +56,7 @@
      */
     sdbusplus::bus_t& bus;
 
-    /*
+    /**
      * Create a BMC Dump
      */
     void createBmcDump();