[SSSD] [PATCH] use stored upn if available

[Sumit Bose]

Hi,

this is the last patch in the series to add the basic support for AD as
a server. With this patch the kerberos backend will use the user
principal name provided by the server to get the TGT. To make the client
side kerberos libraries happy the realm part is always made upper case.

bye,
Sumit