[Samba] Join linux-client trixi not working no dns update

[r.barclay at habmalnefrage.de]

Hi Stefan, 

I've been getting a DNS error on client domain join since years, since setting up my domain.
But I've always just ignored it since everything works fine in my case nevertheless. 
I started the domain back in Debian 10 days with the Debian standard packages.

Yours, 
Reg