Fix for pr3064375.

The search for similar events, used to elide duplicates, was ignoring
the event edge sensitivity. This allowed events that should have been
triggered on different edges of the same signal to be merged.

net_event.cc

@@ -124,6 +124,9 @@ unsigned NetEvent::nexpr() const
 
 static bool probes_are_similar(NetEvProbe*a, NetEvProbe*b)
 {
+      if ( a->edge() != b->edge() )
+            return false;
+
       set<const Nexus*> aset;
       for (unsigned idx = 0 ; idx < a->pin_count() ; idx += 1)
 	    aset .insert( a->pin(idx).nexus() );
@@ -454,4 +457,3 @@ NetProc* NetEvWait::statement()
 {
       return statement_;
 }
-