Whilst in the process of fixing outstanding function-pointer casts in the

LHASH code, this evil was uncovered. The cast was obscuring the fact that
the function was prototyped to take 2 parameters when in fact it is being
used as a callback that should take only one. Anyway, the function itself
ignores the second parameter (thankfully). A proper cure is on the way but
for now this corrects the inconsistency.