Add callback support to triggerable actions

Change-Id: Icc27fbe9403eda418f41e12c76af7f3216f4b72a
Signed-off-by: William A. Kennington III <wak@google.com>
diff --git a/bmc/skip_action.cpp b/bmc/skip_action.cpp
index 4392e97..f1a67e0 100644
--- a/bmc/skip_action.cpp
+++ b/bmc/skip_action.cpp
@@ -26,4 +26,21 @@
     return std::make_unique<SkipAction>();
 }
 
+bool SkipAction::trigger()
+{
+    if (cb)
+    {
+        cb(*this);
+    }
+    return true;
+}
+
+void SkipAction::abort()
+{}
+
+ActionStatus SkipAction::status()
+{
+    return ActionStatus::success;
+}
+
 } // namespace ipmi_flash