spice: init dcl before registering qxl interface

Without this spice might callback into qemu before ssd->dcl.con is
initialized, resulting in a segfault due to NULL pointer dereference.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>

ui/spice-display.c

@@ -775,14 +775,14 @@ static void qemu_spice_display_init_one(QemuConsole *con)
 
     qemu_spice_display_init_common(ssd);
 
+    ssd->dcl.ops = &display_listener_ops;
+    ssd->dcl.con = con;
+
     ssd->qxl.base.sif = &dpy_interface.base;
     qemu_spice_add_display_interface(&ssd->qxl, con);
     assert(ssd->worker);
-
     qemu_spice_create_host_memslot(ssd);
 
-    ssd->dcl.ops = &display_listener_ops;
-    ssd->dcl.con = con;
     register_displaychangelistener(&ssd->dcl);
 }