Fix new table bucketing during unserialization

[luojiuuuuu]

Issue: Anyone upgrading will have a lot of their new table data lost, even if they're not using an asmap.

Expect behavior: We unnecessarily rebucket when reading a peers.dat.

Actual behavior: The code currently rebuckets entries (losing the additional bucket positions) if the asmap checksum changes.

For specific information please refer to the bitcoin project bug issue bitcoin#20557, I found the same bug code in litecoin which has not been fixed yet.