Fixed erroneous use of HOST_SETTINGS in utils.robot.

The correct variable name is HOST_SETTING (singular).
Resolves openbmc/openbmc-test-automation#492

Change-Id: I2b659a56989034c580c8e44d0e539d2919a6ee84
Signed-off-by: Sridevi Ramesh <sridevra@in.ibm.com>
diff --git a/lib/utils.robot b/lib/utils.robot
index 002b6d8..b8d05ed 100755
--- a/lib/utils.robot
+++ b/lib/utils.robot
@@ -709,7 +709,7 @@
 
 Get Auto Reboot
     [Documentation]  Returns auto reboot setting.
-    ${setting}=  Read Attribute  ${HOST_SETTINGS}  auto_reboot
+    ${setting}=  Read Attribute  ${HOST_SETTING}  auto_reboot
     [Return]  ${setting}
 
 
@@ -720,7 +720,7 @@
 
     ${valueDict}=  Set Variable  ${setting}
     ${data}=  Create Dictionary  data=${valueDict}
-    Write Attribute  ${HOST_SETTINGS}  auto_reboot  data=${data}
+    Write Attribute  ${HOST_SETTING}  auto_reboot  data=${data}
     ${current_setting}=  Get Auto Reboot
     Should Be Equal  ${current_setting}  ${setting}