diamondd: Fix faulty comment regarding hashes of attributes
diamondd: Fix faulty comment regarding hashes of attributes

Change faulty comment regarding hashes of attributes. The hashes are
still MD5s, not SHA-256s.

cmusatyalab/opendiamond,cmusatyalab/opendiamond,cmusatyalab/opendiamond,cmusatyalab/opendiamond,cmusatyalab/opendiamond