Adding a test case to Disable DHCPv6

    Changes:
        Adding a test case to Disable DHCPv6 and Verify

    Tested:
        Ran and Tested on BMC Environment.

Change-Id: I1313f36084f629e3ced68824ac93a8f8b676ccbd
Signed-off-by: Vishal Kulkarni <kvishal@in.ibm.com>
diff --git a/redfish/managers/test_bmc_ipv6.robot b/redfish/managers/test_bmc_ipv6.robot
index d8b5f20..ac97dff 100644
--- a/redfish/managers/test_bmc_ipv6.robot
+++ b/redfish/managers/test_bmc_ipv6.robot
@@ -122,6 +122,11 @@
 
     Set And Verify DHCPv6 Property  Enabled
 
+Disable DHCPv6 Property On BMC And Verify
+    [Documentation]  Disable DHCPv6 property on BMC and verify.
+    [Tags]  Disable_DHCPv6_Property_On_BMC_And_Verify
+
+    Set And Verify DHCPv6 Property  Disabled
 
 Configure Invalid Static IPv6 And Verify
     [Documentation]  Configure invalid static IPv6 and verify.