monitor: Capture BMC dumps on fan/ambient shutdowns

When fan-monitor or sensor-monitor generates an EPOW, this change
creates a BMC dump after the system is powered off and all error logs
are created.

Change-Id: Iacdd2d2b388e79988e2536d52497f0e697e1d444
Signed-off-by: Mike Capps <mikepcapps@gmail.com>
diff --git a/monitor/system.hpp b/monitor/system.hpp
index 3997807..8c1bb44 100644
--- a/monitor/system.hpp
+++ b/monitor/system.hpp
@@ -132,6 +132,11 @@
      */
     void inventoryOnlineCb(sdbusplus::message::message& msg);
 
+    /**
+     * @brief Create a BMC Dump
+     */
+    void createBmcDump() const;
+
     /* The mode of fan monitor */
     Mode _mode;