Remove the outpadata field from astgs_request_t, because it's not something we
wish to expose publically (yet it is something that Samba needs in the
client_access plugin API, to add Windows error information).
Instead, allocate rep->padata at the start of AS/TGS request handling, and
ensure it is valid for the lifetime of the request until it is encoded (at
which point it will be freed and set to NULL if zero length, to avoid sending a
zero length METHOD-DATA to the client).
(The previous approach of setting rep->padata to point to &r->outpadata was
fragile, because it required clearing the pointer before freeing the KDC-REP.)
b6be850e0d