savevm: Add DeviceState param

When available, we'd like to be able to access the DeviceState
when registering a savevm.  For buses with a get_dev_path()
function, this will allow us to create more unique savevm
id strings.

Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
diff --git a/hw/stellaris_enet.c b/hw/stellaris_enet.c
index d1d755e..330a9d6 100644
--- a/hw/stellaris_enet.c
+++ b/hw/stellaris_enet.c
@@ -389,7 +389,7 @@
 {
     stellaris_enet_state *s = DO_UPCAST(NICState, nc, nc)->opaque;
 
-    unregister_savevm("stellaris_enet", s);
+    unregister_savevm(&s->busdev.qdev, "stellaris_enet", s);
 
     cpu_unregister_io_memory(s->mmio_index);
 
@@ -419,7 +419,7 @@
     qemu_format_nic_info_str(&s->nic->nc, s->conf.macaddr.a);
 
     stellaris_enet_reset(s);
-    register_savevm("stellaris_enet", -1, 1,
+    register_savevm(&s->busdev.qdev, "stellaris_enet", -1, 1,
                     stellaris_enet_save, stellaris_enet_load, s);
     return 0;
 }