Add Version AlreadyExists Error

Heard from users it is hard to know why the image failed to upload
in this case.

Will use when the version is already on the device.

Change-Id: Ibbbda073e16c2ca45700d5e22b368c07d440d412
Tested: Built with phosphor-bmc-code-mgmt and bmcweb changes and saw the error.
Signed-off-by: Gunnar Mills <gmills@us.ibm.com>
diff --git a/xyz/openbmc_project/Software/Version.errors.yaml b/xyz/openbmc_project/Software/Version.errors.yaml
index 4d63a57..e62ee4b 100644
--- a/xyz/openbmc_project/Software/Version.errors.yaml
+++ b/xyz/openbmc_project/Software/Version.errors.yaml
@@ -5,3 +5,6 @@
     error include creating logging events and providing information on
     implementation reactions such as when the system is prevented from powering
     on if a minimum version level is not met.
+- name: AlreadyExists
+  description: >
+    This image version already exists on the device