Support rsa-sha2-512 hostkey

Hi,

sshd in fedora33 does not accept ssh-rsa by default. The error is 'Server refused our key.'
Putty implemented rsa-sha2-512 in the latest master (after 0.74 release).
Please consider updating it to some snapshot or when 0.75 is available.

Sorry for my late answer.

This request has been added to the tracker:
https://winscp.net/tracker/1952
You can vote for it there.

We will definitely upgrade to PuTTY 0.75 once it is available. If there's a popular demand, we may upgrade to a snapshot even before the 0.75 release.