Incorrect machine learning backend PHP config information provided in message

When training a model on the command line, the process bails after a while indicating that it should be run with mlbackend_php_no_memory_limit set to remove memory limits. However, that configuration option appears nowhere in the code and therefore has no effect. The correct configuration option is mlbackend_php_no_evaluation_limits.

To reproduce the problem:

With a large data set, run admin/tool/analytics/cli/evaluate_model.php and wait a long time. Eventually, it will exit with something like this:

!! Only part of the dataset has been evaluated due to its size. Set $CFG->mlbackend_php_no_memory_limit if you are confident that your system can cope with a 40.7MB dataset. !!

Set that configuration property to true in config.php as instructed in the message above and run again. The problem persists!

Change the configuration option that you've set from mlbackend_php_no_memory_limit to mlbackend_php_no_evaluation_limits. Run again. It still fails because of a missing global $CFG; in processor.php.

Now apply the patch (which I'll provide below) and try again. The message is no longer there and results are complete.