Add error message to build description

Change-Id: Ifffce007fbe9d3bc47ea57c30ee652b5e0bdb680
diff --git a/ovs-gateway-upgrade.groovy b/ovs-gateway-upgrade.groovy
index 70037a4..5301a0a 100644
--- a/ovs-gateway-upgrade.groovy
+++ b/ovs-gateway-upgrade.groovy
@@ -148,6 +148,7 @@
     } catch (Throwable e) {
         // If there was an error or exception thrown, the build failed
         currentBuild.result = "FAILURE"
+        currentBuild.description = e.message
         throw e
     }
 }