Use the common timer class

The common timer class from sdbusplus offers all the timer goodness that
we currently use. The unit test is also no longer needed (and has been
added to sdbusplus's version of the timer.hpp implementation).

Change-Id: I278817489433a29ca739f70fdacd8bb897797d66
Signed-off-by: Vernon Mauery <vernon.mauery@linux.intel.com>
diff --git a/softoff/softoff.hpp b/softoff/softoff.hpp
index b7555e3..1c9341b 100644
--- a/softoff/softoff.hpp
+++ b/softoff/softoff.hpp
@@ -2,11 +2,10 @@
 
 #include "config.h"
 
-#include "timer.hpp"
-
 #include <functional>
 #include <sdbusplus/bus.hpp>
 #include <sdbusplus/server/object.hpp>
+#include <sdbusplus/timer.hpp>
 #include <xyz/openbmc_project/Control/Host/server.hpp>
 #include <xyz/openbmc_project/Ipmi/Internal/SoftPowerOff/server.hpp>
 namespace phosphor