[SSSD] [PATCH] Fixed subdomain-related issue in re_expression matching

[Jan Zelený]

One part of the matching was to check whether domain part of fully
qualified name is a name of a domain or any of its subdomains. The
problem is that at the time of first request we don't yet have lists of
subdomains.

One solution would be to issue a request to data provider, asking for a
list of subdomains but mixing subdomain logic with re_expression
matching doesn't seem right. Therefore this patch deletes the check for
specific domain name, leaving only check for a specific format.

Thanks
Jan