mem-ruby: Reset Ruby Sequencer Outstanding Requests stats

Change-Id: I14b106e0eb7abd9c14badeedf35d6d1c9f198f98
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/22446
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Tested-by: kokoro <noreply+kokoro@google.com>

src/mem/ruby/system/Sequencer.cc

@@ -114,6 +114,7 @@ Sequencer::wakeup()
 
 void Sequencer::resetStats()
 {
+    m_outstandReqHist.reset();
     m_latencyHist.reset();
     m_hitLatencyHist.reset();
     m_missLatencyHist.reset();