The API which is used to list supported hash flags verifies
hash algorithm choice before writing the output. This check
is based on a switch() statement which has only two options
and no distinctive actions to be conducted for each of them.
Use simpler code instead of switch() to improve readability.
Submitted by: Ivan Malov <ivan.malov at oktetlabs.ru>
Sponsored by: Solarflare Communications, Inc.