ipaserver/dcerpc.py: enforce SMB encryption on LSA pipe if available
We want to always use SMB encryption if it is possible on LSA pipe as we
are going to pass what accounts to a plain-text content within
CreateTrustedDomainEx2 call.
The catch is that older Samba version might not have a way to enforce
this and we need fall back to work with existing connection then.
Fixes: https://pagure.io/freeipa/issue/8655
Signed-off-by: Alexander Bokovoy <abokovoy@redhat.com>
Reviewed-By: Rob Crittenden <rcritten@redhat.com>