smokeping.fcgi dies if an RRD cannot be locked

[themsley-voiceflex]

If an RRD cannot be locked for RRD::info or RRD::fetch then the fcgid process dies with a 500 error and has to be respawned. The following patch changes the code to retry the info/fetch up to 20 times at 0.2s intervals (total 4s) to avoid an expensive respawn. This may not be the correct place to add this retry, it might be better in the RRD::info itself but it works and stops smokeping using 800% cpu!

smokeping-2.8.2-locking-retry.PATCH