hook_aggregator_process_info() - remove $feed from docs

Looks like the $feed argument for hook_aggregator_process_info() is a typo, started here Pluggable architecture for aggregator.module.

At first it was hook_aggregator_process($op, $feed = NULL) with $opt being 'save', 'unique', 'info', like it was in Drupal 6. Then each $op become its own hook functions while keeping the $feed argument.

In the original function, the $op == 'info' do not make use of the $feed argument:

    case 'info':
      return array(
        'title' => t('Aggregator Light'),
        'description' => t('Creates lightweight records of feed items.'),
     );

Also, the aggregator module itself implements hook_aggregator_process_info() without $feed argument.

/**
 * Implementation of hook_aggregator_process_info().
 */
function aggregator_aggregator_process_info() {
  return array(
    'title' => t('Default processor'),
    'description' => t('Creates lightweight records from feed items.'),
  );
}

#1930274: Convert aggregator processors and parsers to plugins takes care of that for d8, moving to d7

Here's a patch.

thanks!