Fix hashes being stored as passwords in smb_login

From @rsmudge in the [redmine bug](https://dev.metasploit.com/redmine/issues/8841):
> Steps to reproduce:
> 1. Dump password hashes on a Windows host
> 2. Create a userpass.txt file with one username/hash per line
> 3. Launch smb_login against the same host
> 4. observe the new "password" entries in the creds table.