[zfs] adding hostid

using ZFS in combination with dracut exposed a bug on system updates hostid from the Live session does not match hostid installed, thus zpool id no longer matches id created by dracut in the kernel img
to work around this, the zfs module now uses zgenhostid to create a hostid

src/modules/zfs/ZfsJob.cpp

@@ -241,6 +241,13 @@ ZfsJob::exec()
             }
         }
 
+        // Generate the zfs hostid file
+        auto i = system->runCommand( { "zgenhostid" }, std::chrono::seconds( 3 ) );
+        if ( i.getExitCode() != 0 )
+        {
+            cWarning() << "Failed to create /etc/hostid";
+        }
+
         // Create the zpool
         ZfsResult zfsResult;
         if ( encrypt )