Redfish: Specify which library to use for 'Get Redfish session info'

Changes:
 - Specify that Keyword 'Get Redfish Session Info' is called from Library Redfish_Utils

Tested:
  - The Keyword 'Delete All Redfish Sessions' is called from the test suite.

Change-Id: I0811910e4e2606f9bd235c17396328073990abf5
Signed-off-by: Sagar Anand <sagaranand@in.ibm.com>
diff --git a/lib/bmc_redfish_utils.robot b/lib/bmc_redfish_utils.robot
index fab151a..9fceae1 100644
--- a/lib/bmc_redfish_utils.robot
+++ b/lib/bmc_redfish_utils.robot
@@ -113,7 +113,7 @@
 Delete All Redfish Sessions
     [Documentation]  Delete all active redfish sessions.
 
-    ${saved_session_info}=  Get Redfish Session Info
+    ${saved_session_info}=  Redfish_Utils.Get Redfish Session Info
 
     ${resp_list}=  Redfish_Utils.Get Member List
     ...  /redfish/v1/SessionService/Sessions