fs/locks.c: replace seq_printf by seq_puts

Replace seq_printf where possible

Cc: Jeff Layton <jlayton@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Jeff Layton <jlayton@poochiereds.net>