[SSSD] [PATCH] simple access provider: allow fully qualified names

[Pavel Březina]

https://fedorahosted.org/sssd/ticket/2026

I created a separate ticket to support subdomain users and groups in 
allow/deny lists.
https://fedorahosted.org/sssd/ticket/2034

There is a bug in PAC responder at the moment which makes simple access 
provider to always deny access to subdomain users. PAC responder 
currently fails to resolve group membership, thus we get error in access 
provider when looking up groups and access is denied. Jakub will look 
into this.