r25133: Fix sasl wrapping (for ldap sign&seal).

r25133: Fix sasl wrapping (for ldap sign&seal).

The gss_import_name() broke as we switched from the internal MIT OID
"gss_nt_krb5_principal" to "GSS_KRB5_NT_PRINCIPAL_NAME" and didn't switch from
passing the krb5_principal (or better: a pointer to that, see MIT's "*HORRIBLE*
bug") to pass the string principal directly.

Jerry, Jeremy, neither I could figure out the need of passing in a
krb5_principal at all nor could I reproduce the crash you were seeing.

I sucessfully tested the code (now importing a string) with MIT 1.2.7, 1.3.6,
1.4.3, 1.5.1, 1.6.1 and Heimdal 0.7.2, 1.0, 1.0.1.

Guenther
(This used to be commit cb2dc715e33467c8b588161e816e72a948f6860c)