spice: drop incorrect vm_change_state_handler() opaque

The spice_server pointer is a global variable and
vm_change_state_handler() therefore does not use its opaque parameter.

The vm change state handler is added with a pointer to the spice_server
pointer.  This is useless and we probably would not want 2 levels of
pointers.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Uri Lublin <uril@redhat.com>

ui/spice-core.c

diff --git a/ui/spice-core.c b/ui/spice-core.c
index 3e44779..d83de2a 100644
--- a/ui/spice-core.c
+++ b/ui/spice-core.c
@@ -709,7 +709,7 @@
     qemu_spice_input_init();
     qemu_spice_audio_init();
 
-    qemu_add_vm_change_state_handler(vm_change_state_handler, &spice_server);
+    qemu_add_vm_change_state_handler(vm_change_state_handler, NULL);
 
     g_free(x509_key_file);
     g_free(x509_cert_file);
@@ -736,8 +736,7 @@
          */
         spice_server = spice_server_new();
         spice_server_init(spice_server, &core_interface);
-        qemu_add_vm_change_state_handler(vm_change_state_handler,
-                                         &spice_server);
+        qemu_add_vm_change_state_handler(vm_change_state_handler, NULL);
     }
 
     return spice_server_add_interface(spice_server, sin);