PEL 401 HTTP response

Changes:
   - Add redfish login to the keyword before purging error logs

Tested:
   Tested openpower/pel/test_bmc_pel.robot

Change-Id: I72ec52dfebbfc8eced9610406393a14b6e762940
Signed-off-by: George Keishing <gkeishin@in.ibm.com>
diff --git a/openpower/pel/test_bmc_pel.robot b/openpower/pel/test_bmc_pel.robot
index aa46788..cad299d 100644
--- a/openpower/pel/test_bmc_pel.robot
+++ b/openpower/pel/test_bmc_pel.robot
@@ -675,6 +675,8 @@
     #                                     log type when maximum count/log size is reached.
     #                                     The maximum error log count is 3000.
 
+    Redfish.Login
+
     # Initially remove all logs. Purging is done to ensure that, only specific logs are present
     # in BMC during the test.
     Redfish Purge Event Log