Exit firmware update if the image is already functional on BMC

Output:
MANIFEST
.image_version:                  2.9.0-dev-539-g4d7666098
Issuing: cat /etc/os-release
..functional_version:            2.9.0-dev-539-g4d7666098

Change-Id: Ic2a19ba01b6cbf3903cea3bb7bff7aee49cab7b8
Signed-off-by: George Keishing <gkeishin@in.ibm.com>
diff --git a/redfish/extended/redfish_bmc_code_update.robot b/redfish/extended/redfish_bmc_code_update.robot
index 77194f3..ebec8a7 100644
--- a/redfish/extended/redfish_bmc_code_update.robot
+++ b/redfish/extended/redfish_bmc_code_update.robot
@@ -45,6 +45,10 @@
     ${functional_version}=  Set Variable  ${bmc_release_info['version_id']}
     Rprint Vars  functional_version
 
+    # Check if the existing firmware is functional.
+    Pass Execution If  '${functional_version}' == '${image_version}'
+    ...  The existing ${image_version} firmware is already functional.
+
     Run Keyword If  not ${FORCE_UPDATE}
     ...  Activate Existing Firmware  ${image_version}
     Redfish Update Firmware