From:  Stephen Rothwell <sfr@canb.auug.org.au>

  This allows some architecture to override the generic implementations
  on {get,put}_compat_flock64 as some of them (ia64 and maybe x86_64)
  will take alignment faults when accessing the loff_t members of struct
  compat_flock64.

  Requested by David Mosberger, modified by Dave Miller.