Fix an error in the definition of the sortedness condition for Equihash.
Fix an error in the definition of the sortedness condition for Equihash.

Signed-off-by: Daira Hopwood <cd7d43d5556a38ce626d53826fddc46adc597539@jacaranda.org>

zcash/zips,zcash/zips,zcash/zips,zcash/zips