control: Add power on/off triggers

Add two new classes of triggers: powerOn and powerOff.  They are only
called during the power on and power off state changes, respectively.

They behave the same as the existing init trigger.

Signed-off-by: Matt Spinler <spinler@us.ibm.com>
Change-Id: I9d39210843192b9c343c7838c604fcce7c8d3f3d
diff --git a/control/json/triggers/trigger.hpp b/control/json/triggers/trigger.hpp
index ced50d7..c8847c4 100644
--- a/control/json/triggers/trigger.hpp
+++ b/control/json/triggers/trigger.hpp
@@ -29,6 +29,8 @@
 static const std::map<std::string, createTrigger> triggers = {
     {"timer", timer::triggerTimer},
     {"signal", signal::triggerSignal},
-    {"init", init::triggerInit}};
+    {"init", init::triggerInit},
+    {"poweron", init::triggerInit},
+    {"poweroff", init::triggerInit}};
 
 } // namespace phosphor::fan::control::json::trigger