Revert "systemc: Fix clang9 linker error"

This reverts commit 80a2636983.

Change-Id: I24c69d1a5a54ac8b8d5713314f6e91e5a6263c26
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/29395
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Tested-by: kokoro <noreply+kokoro@google.com>

src/systemc/core/scheduler.cc

@@ -479,13 +479,6 @@ Scheduler::scheduleStop(bool finish_delta)
     schedule(&stopEvent);
 }
 
-void
-Scheduler::scheduleTimeAdvancesEvent()
-{
-    if (!traceFiles.empty() && !timeAdvancesEvent.scheduled())
-        schedule(&timeAdvancesEvent);
-}
-
 void
 Scheduler::trace(bool delta)
 {

src/systemc/core/scheduler.hh

@@ -459,7 +459,12 @@ class Scheduler
 
     void timeAdvances() { trace(false); }
     EventWrapper<Scheduler, &Scheduler::timeAdvances> timeAdvancesEvent;
-    void scheduleTimeAdvancesEvent();
+    void
+    scheduleTimeAdvancesEvent()
+    {
+        if (!traceFiles.empty() && !timeAdvancesEvent.scheduled())
+            schedule(&timeAdvancesEvent);
+    }
 
     uint64_t _numCycles;
     uint64_t _changeStamp;