Explicitly label .origin files as configuration

subscription-manager has a daemon that runs in a confined domain,
and it doesn't have permission to write usr_t, which is the default
label of /ostree/deploy/$osname/deploy.

A better long term fix is probably to move the origin file into the
deployment root as /etc/ostree/origin.conf or so.

In the meantime, let's ensure the .origin files are labeled as
configuration.

src/libostree/ostree-sysroot.c

@@ -63,6 +63,7 @@ ostree_sysroot_finalize (GObject *object)
   OstreeSysroot *self = OSTREE_SYSROOT (object);
 
   g_clear_object (&self->path);
+  g_clear_object (&self->sepolicy);
 
   G_OBJECT_CLASS (ostree_sysroot_parent_class)->finalize (object);
 }