CVE-2021-3738 s4:rpc_server/drsuapi: make use of assoc_group aware dcesrv_samdb_connect_as_*() helpers
This avoids a crash that's triggered by windows clients using
DsCrackNames across multiple connections within an association group
on the same DsBind context(policy) handle.
It also improves the auditing for the dcesrv_samdb_connect_as_system() case.
BUG: https://bugzilla.samba.org/show_bug.cgi?id=14468
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>