Use control.xml to set DNS.dhcp_hostname (bnc#870896)

See also related pull requests in https://github.com/ancorgs/skelcd-control-SLED and https://github.com/ancorgs/skelcd-control-SLES
OK, It seems that ProductControl takes care itself to set ProducFeatures: https://github.com/yast/yast-yast2/blob/master/library/control/src/modules/ProductControl.rb#L298-L307

It's not your problem, that the code is a bit spaghetti-like :-/

Lowering to NTH