base,cpu,dev: Add a level of indirection for ListenSockets.

This makes room for there to be different implementations for different
types of sockets.

Change-Id: I8c959e2c3400caec8242e693e11330e072bc2c5f
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/69162
Reviewed-by: Yu-hsin Wang <yuhsingw@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Maintainer: Gabe Black <gabe.black@gmail.com>

src/cpu/nativetrace.cc

@@ -39,14 +39,14 @@ namespace gem5
 namespace trace {
 
 NativeTrace::NativeTrace(const Params &p)
-    : ExeTracer(p), native_listener(p.name, 8000)
+    : ExeTracer(p), native_listener(listenSocketInetConfig(8000).build(p.name))
 {
     if (ListenSocket::allDisabled())
         fatal("All listeners are disabled!");
 
-    native_listener.listen();
+    native_listener->listen();
 
-    fd = native_listener.accept();
+    fd = native_listener->accept();
 }
 
 void

src/cpu/nativetrace.hh

@@ -71,7 +71,7 @@ class NativeTrace : public ExeTracer
   protected:
     int fd;
 
-    ListenSocket native_listener;
+    ListenSocketPtr native_listener;
 
   public: