[users] Move the hostname-setting config

- The configuration for writing the hostname (to /etc/hostname,
  to /etc/hosts and possibly to systemd-hostname) is read-only,
  because it comes from the config file and won't change after.

src/modules/users/UsersViewStep.h

@@ -20,8 +20,6 @@
 #ifndef USERSPAGEPLUGIN_H
 #define USERSPAGEPLUGIN_H
 
-#include "SetHostNameJob.h"
-
 #include "DllMacro.h"
 #include "utils/PluginFactory.h"
 #include "viewpages/ViewStep.h"
@@ -61,8 +59,6 @@ private:
     UsersPage* m_widget;
     QList< Calamares::job_ptr > m_jobs;
 
-    SetHostNameJob::Actions m_actions;
-
     Config* m_config;
 };