added support for power driver setting

Change-Id: I96323cd883f2a42878fa981a487e70e5122eaefe
diff --git a/README.rst b/README.rst
index 021b8c4..250ea82 100644
--- a/README.rst
+++ b/README.rst
@@ -112,6 +112,8 @@
             power_address: '192.168.10.10'
             power_user: bmc_user
             power_password: bmc_password
+            #Optional (for legacy HW)
+            power_driver: LAN
           distro_series: xenial
           hwe_kernel: hwe-16.04
       devices:
diff --git a/_modules/maas.py b/_modules/maas.py
index 3c9b55e..63fb098 100644
--- a/_modules/maas.py
+++ b/_modules/maas.py
@@ -365,6 +365,8 @@
             'power_type': machine_data.get('power_type', 'ipmi'),
             'power_parameters_power_address': power_data['power_address'],
         }
+        if 'power_driver' in power_data:
+            data['power_parameters_power_driver'] = power_data['power_driver']
         if 'power_user' in power_data:
             data['power_parameters_power_user'] = power_data['power_user']
         if 'power_password' in power_data: