s3-auth: use full 16byte session key in make_user_info_netlogon_interactive().

s3-auth: use full 16byte session key in make_user_info_netlogon_interactive().

Patch from Jeremy.

With this patch, I was able to join Windows 7 RC to a Samba3 DC, and login into a
Samba 3 Domain.

There are still two registry settings required:

        HKLM\System\CCS\Services\LanmanWorkstation\Parameters
	            DWORD  DomainCompatibilityMode = 1
		    DWORD  DNSNameResolutionRequired = 0

Do *not* modify the other netlogon registry parameters that were passed around,
they weaken security.

Guenther
(cherry picked from commit b5097d54cb74ca0ea328f9e029562f65f4a01134)