migration: Free removed SaveStateEntry

This fixes LeakSanitizer warnings.

Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Reviewed-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Fabiano Rosas <farosas@suse.de>
diff --git a/migration/savevm.c b/migration/savevm.c
index deb5783..85958d7 100644
--- a/migration/savevm.c
+++ b/migration/savevm.c
@@ -874,6 +874,8 @@
 
     if (se) {
         savevm_state_handler_remove(se);
+        g_free(se->compat);
+        g_free(se);
     }
     return vmstate_register(obj, instance_id, vmsd, opaque);
 }