Add hardware_info dictionary to Machine

Author: mpontillo

maas/client/viscera/machines.py

@@ -363,6 +363,7 @@ class Machine(Node, metaclass=MachineType):
     netboot = ObjectField.Checked("netboot", check(bool), readonly=True)
     osystem = ObjectField.Checked("osystem", check(str), readonly=True)
     owner_data = ObjectField.Checked("owner_data", check(dict), check(dict))
+    hardware_info = ObjectField.Checked("hardware_info", check(dict), check(dict), readonly=True)
     status = ObjectField.Checked("status", to(NodeStatus), readonly=True)
     status_action = ObjectField.Checked(
         "status_action", check_optional(str), readonly=True