dnsserver: Return access denied to the caller if the user was not a DNS admin
This is not a proper fix to match Windows, but at the very least, it
should be more obvious to users (using samba-tool for instance), that
the user needs to be given more access or that they should use the
administrator.
Windows seems to deny access altogether by returning a fault after they
have bound to the pipe and actually sent an operation.
BUG: https://bugzilla.samba.org/show_bug.cgi?id=13771
Signed-off-by: Garming Sam <garming@catalyst.net.nz>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>