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.cpp b/softoff/softoff.cpp
index 921536f..803efc0 100644
--- a/softoff/softoff.cpp
+++ b/softoff/softoff.cpp
@@ -103,7 +103,7 @@
 // Starts a timer
 int SoftPowerOff::startTimer(const std::chrono::microseconds& usec)
 {
-    return timer.startTimer(usec);
+    return timer.start(usec);
 }
 
 // Host Response handler
@@ -115,7 +115,7 @@
     {
         // Disable the timer since Host has quiesced and we are
         // done with soft power off part
-        auto r = timer.setTimer(SD_EVENT_OFF);
+        auto r = timer.stop();
         if (r < 0)
         {
             log<level::ERR>("Failure to STOP the timer",