Added retries for db_sync

If db sync fails, it is never retried leading to errors. So, this
patch adds retries for db_sync to avoid sync fails.

Change-Id: I108a33ed8bacc12c9b7cc00e603c78ea51c948b2
Closes-Bug: #1628580

manifests/db/sync.pp

@@ -21,6 +21,8 @@ class cinder::db::sync(
     path        => '/usr/bin',
     user        => 'cinder',
     refreshonly => true,
+    try_sleep   => 5,
+    tries       => 10,
     logoutput   => 'on_failure',
     subscribe   => [
       Anchor['cinder::install::end'],