Only check current boot failures for standby

The BMC health check looks at the journal to check for application
failures. The journal sometimes contains errors from the previous
boot. With this change the health check only looks at the last boot
for errors in the journal, rather than previous boots.

Change-Id: I6ff341da1dbc695bb92c72be9ca3f0e68e80c3b5
Signed-off-by: Charles Paul Hofer <Charles.Hofer@ibm.com>
diff --git a/extended/standby_bmc.robot b/extended/standby_bmc.robot
index 9d4df16..889c996 100644
--- a/extended/standby_bmc.robot
+++ b/extended/standby_bmc.robot
@@ -120,7 +120,7 @@
 
     ${error_regex}=  Escape Bash Quotes  ${error_regex}
     ${journal_log}  ${stderr}  ${rc}=  BMC Execute Command
-    ...  journalctl --no-pager | egrep '${error_regex}'  ignore_err=1
+    ...  journalctl -b --no-pager | egrep '${error_regex}'  ignore_err=1
 
     Should Be Empty  ${journal_log}