Use CHASSIS_ID to get PowerSupplies info

The correct path is /redfish/v1/Chassis/<chassis>/Power

Tested:
   Ran the suite with -v CHASSIS_ID:2U

Change-Id: I2073cce384f2c8362105b6bddac76bad8d25a928
Signed-off-by: Glukhov Mikhail <mikl@greenfil.ru>
diff --git a/redfish/systems/test_systems_inventory.robot b/redfish/systems/test_systems_inventory.robot
index 3282b32..0ec05c8 100755
--- a/redfish/systems/test_systems_inventory.robot
+++ b/redfish/systems/test_systems_inventory.robot
@@ -210,7 +210,7 @@
     ...  [('ProcessorType', 'Accelerator')]  regex=1
 
     ${power_supplies}=  Redfish.Get Attribute
-    ...  ${REDFISH_CHASSIS_POWER_URI}  PowerSupplies
+    ...  ${REDFISH_CHASSIS_URI}${CHASSIS_ID}/Power  PowerSupplies
 
     [Return]  ${cpu_info}  ${gpu_info}  ${power_supplies}