Some bash versions don't support negative lengths

Fix to make the service string work on these versions of bash too

Change-Id: Ibb9868ea7bf44480be76a8ea9d7d9fbc278a8ef3
diff --git a/functions b/functions
index b8fd688..632cd46 100644
--- a/functions
+++ b/functions
@@ -1116,7 +1116,7 @@
 
     for service in $failures; do
         service=`basename $service`
-        service=${service::-8}
+        service=${service%.failure}
         echo "Error: Service $service is not running"
     done