Set system, chassis, and bmc as global variables

Changes:
  - Add SYSTEM_ID as a global variable and set to default value system
  - Replace redfish/v1/Systems/system to redfish/v1/Systems/SYSTEM_ID
  - Replace redfish/v1/Chassis/chassis to redfish/v1/Chassis/CHASSIS_ID
  - Replace redfish/v1/Managers/bmc to redfish/v1/Managers/MANAGER_ID

Tested:
  - Tested on sandbox with the changes with sample test run with
    sample test ID runs
    1. without SYSTEM_ID provided
    2. with -v SYSTEM_ID:system1
    3. with export SYSTEM_ID=""
    3. with export SYSTEM_ID="system2"

Change-Id: Ifc412b20038cef1eba632caaa6c300be328259bd
Signed-off-by: Wilson Suen <wilsons@supermicro.com>
Signed-off-by: George Keishing <gkeishin@in.ibm.com>
diff --git a/lib/logging_utils.robot b/lib/logging_utils.robot
index 9d6ca1f..bc77fc4 100644
--- a/lib/logging_utils.robot
+++ b/lib/logging_utils.robot
@@ -319,7 +319,7 @@
     [Documentation]  Do Redfish EventLog purge.
 
     ${target_action}=  redfish_utils.Get Target Actions
-    ...  /redfish/v1/Systems/system/LogServices/EventLog/  LogService.ClearLog
+    ...  /redfish/v1/Systems/${SYSTEM_ID}/LogServices/EventLog/  LogService.ClearLog
     Redfish.Post  ${target_action}  body={'target': '${target_action}'}
     ...  valid_status_codes=[${HTTP_OK}, ${HTTP_NO_CONTENT}]
 
@@ -335,7 +335,7 @@
     [Documentation]  Do Redfish PostCodes purge from system.
 
     ${target_action}=  redfish_utils.Get Target Actions
-    ...  /redfish/v1/Systems/system/LogServices/PostCodes/  LogService.ClearLog
+    ...  /redfish/v1/Systems/${SYSTEM_ID}/LogServices/PostCodes/  LogService.ClearLog
     Redfish.Post  ${target_action}  body={'target': '${target_action}'}
     ...  valid_status_codes=[${HTTP_OK}, ${HTTP_NO_CONTENT}]
 
@@ -361,7 +361,7 @@
     #    [Name]:                   POST Code Log Entry
     #    [Severity]:               OK
 
-    ${members}=  Redfish.Get Attribute  /redfish/v1/Systems/system/LogServices/PostCodes/Entries  Members
+    ${members}=  Redfish.Get Attribute  /redfish/v1/Systems/${SYSTEM_ID}/LogServices/PostCodes/Entries  Members
     ...  valid_status_codes=[${HTTP_OK}, ${HTTP_NO_CONTENT}]
 
     [Return]  ${members}