nfsd: don't EXPORT_SYMBOL nfsd4_ssc_init_umount_work()

nfsd4_ssc_init_umount_work() is only used in the nfsd module, so there
is no need to EXPORT it.
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

fs/nfsd/nfs4state.c

@@ -6271,7 +6271,6 @@ void nfsd4_ssc_init_umount_work(struct nfsd_net *nn)
 	INIT_LIST_HEAD(&nn->nfsd_ssc_mount_list);
 	init_waitqueue_head(&nn->nfsd_ssc_waitq);
 }
-EXPORT_SYMBOL_GPL(nfsd4_ssc_init_umount_work);
 
 /*
  * This is called when nfsd is being shutdown, after all inter_ssc