Fix drowning of minor_status code when accepting GSSAPI security context

[jjkeijser]

Fix drowing out of the GSSAPI minor_status code when accepting GSSAPI security context. This fixes the issue during GSSAPI (Kerbos) negotation in case the server is misconfigured. Without the patch, cupsd reports

  Error accepting GSSAPI security context.: Unspecified GSS failure.  Minor code may provide more information, Unknown error 

With the patch, the true GSSAPI error is printed:

  Error accepting GSSAPI security context.: Unspecified GSS failure.  Minor code may provide more information, Request ticket server host/host.example.nl@EXAMPLE.COM kvno 6 not found in keytab; keytab is likely out of date

Signed-off-by: Jan Just Keijser jan.just.keijser@gmail.com