Peter Marschall authored Apr 07, 2020 and Quanah Gibson-Mount committed Apr 21, 2020

* use 'crypto_pwhash_str_alg(..., crypto_pwhash_ALG_ARGON2ID13)' to set
  the algorithm to Argon2.
  According to libsodium's documentation, the original 'crypto_pwhash_str()'
  only guarantees a "memory-hard, CPU-intensive hash function", but not
  necessarily Argon2.  Although in released versions of libsodium Argon2 is
  the only implemented backend, this may chane in the future.
* multiply the 'memory' parameter by 1024 to align it with the libargon2
  implementation. The objective is to have consistent configuration in
  OpenLDAP's pw-argon2 module no matter what backend implementation is used.

Signed-off-by: Peter Marschall <peter@adpm.de>