Add force tags for openpower vmi test suite

Changes:
    - Added force tag directive names

Tested:

    With --include or --exclude  options while running test suite

    Tag names:
       vmi_certificate_test
       vmi_multi_interface_test
       vmi_interface_test

Change-Id: I1879ccc211d45d52a31082e1bb2674274c577e23
Signed-off-by: George Keishing <gkeishin@in.ibm.com>
diff --git a/openpower/ext_interfaces/test_vmi_multiple_interfaces.robot b/openpower/ext_interfaces/test_vmi_multiple_interfaces.robot
index 723101d..1cac17a 100644
--- a/openpower/ext_interfaces/test_vmi_multiple_interfaces.robot
+++ b/openpower/ext_interfaces/test_vmi_multiple_interfaces.robot
@@ -11,6 +11,8 @@
 Test Teardown     FFDC On Test Case Fail
 Suite Teardown    Suite Teardown Execution
 
+Force Tags        vmi_multi_interface_test
+
 *** Variables ***
 
 ${test_ipv4_1}              10.6.6.6