optimize nni-port handling

Change-Id: I957a4a40bbc8386c2b9dcd57837cba0af3549989
diff --git a/tests/functional/Voltha_ONOSHATests.robot b/tests/functional/Voltha_ONOSHATests.robot
old mode 100644
new mode 100755
index 5924981..4922a73
--- a/tests/functional/Voltha_ONOSHATests.robot
+++ b/tests/functional/Voltha_ONOSHATests.robot
@@ -100,9 +100,7 @@
         ${of_id}=    Wait Until Keyword Succeeds    ${timeout}    15s    Validate OLT Device in ONOS
         ...    ${olt_serial_number}
         Set Global Variable    ${of_id}
-        ${nni_port}=    Run Keyword And Continue On Failure    Wait Until Keyword Succeeds    ${timeout}    2s
-        ...    Get NNI Port in ONOS    ${of_id}
-        Set Global Variable    ${nni_port}
+        ${nni_port}=     Wait Until Keyword Succeeds    ${timeout}    2s    Get NNI Port in ONOS    ${of_id}
         ${num_onus}=    Set Variable    ${list_olts}[${I}][onucount]
         Run Keyword If   '${workflow}' == 'ATT'    Wait Until Keyword Succeeds    ${timeout}    2s
         ...    Perform Sanity Test Per OLT    ${of_id}    ${nni_port}    ${olt_serial_number}    ${num_onus}