CRM-14472 - when returning getPCPList(), query correct table for contribution-type vs. event-type PCPs

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* CRM-14472: Credit offline contribution to an event PCP
  https://issues.civicrm.org/jira/browse/CRM-14472
Merge pull request #2909 from jake-mw/crm-14472

CRM-14472 - query correct table for contribution-type vs. event-type PCPs