ncpfs: rcu-delay unload_nls() and freeing ncp_server

makes ->d_hash() and ->d_compare() safety in RCU mode independent
from vfsmount_lock.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/ncpfs/ncp_fs_sb.h

@@ -38,7 +38,7 @@ struct ncp_mount_data_kernel {
 };
 
 struct ncp_server {
-
+	struct rcu_head rcu;
 	struct ncp_mount_data_kernel m;	/* Nearly all of the mount data is of
 					   interest for us later, so we store
 					   it completely. */