Fixed missing parameter when using ipmi user priv

When execute inband command user priv <user id> <privilege level>
it will return 'IPMI command failed: Unknown (0x82)'
Because it missing a parameter <channel number>
User Commands:
priv         <user id> <privilege level> [<channel number>]
                     Privilege levels:
                      * 0x1 - Callback
                      * 0x2 - User
                      * 0x3 - Operator
                      * 0x4 - Administrator
                      * 0x5 - OEM Proprietary
                      * 0xF - No Access

Signed-off-by: Tony Lee <tony.lee@quantatw.com>
Change-Id: I11cb0789ffaec27d516be8fb034e7d37c5c3d96a
diff --git a/redfish/account_service/test_ipmi_redfish_user.robot b/redfish/account_service/test_ipmi_redfish_user.robot
index 6df08fe..9877744 100644
--- a/redfish/account_service/test_ipmi_redfish_user.robot
+++ b/redfish/account_service/test_ipmi_redfish_user.robot
@@ -166,7 +166,7 @@
 
     # Change user privilege to opetrator using IPMI.
     Run IPMI Standard Command
-    ...  user priv ${userid} ${operator_level_priv}
+    ...  user priv ${userid} ${operator_level_priv} ${CHANNEL_NUMBER}
 
     # Verify new user privilege level via Redfish.
     ${privilege}=  Redfish_Utils.Get Attribute