Check return code when doing PDU reset

PDU (Power Distribution Unit) will return HTTP_OK if successful.

Resolves openbmc/openbmc-test-automation#971
Change-Id: I153d9019ba3170fbb97522dc3ddd458cc4481a2b
Signed-off-by: Steven Sombar <ssombar@us.ibm.com>
diff --git a/lib/pdu/synaccess.robot b/lib/pdu/synaccess.robot
index 98f7211..ff71089 100644
--- a/lib/pdu/synaccess.robot
+++ b/lib/pdu/synaccess.robot
@@ -14,3 +14,6 @@
 Power Cycle
     Connect and Login
     ${ret}=    Get Request    pdu    /cmd.cgi?$A4 ${PDU_SLOT_NO}
+    ${error_message}=  Catenate  Power cycle of slot ${PDU_SLOT_NO} failed.
+    ...  PDU returned RC=${ret}.
+    Should Be Equal As Strings  ${ret}  ${HTTP_OK}  msg=${error_message}