CRM-12689 related fix

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* CRM-12689: Generalize Additional/limit recipients in Scheduled reminders
  http://issues.civicrm.org/jira/browse/CRM-12689
Merge pull request #1421 from monishdeb/CRM-12689-QA-fix

CRM-12689 related fix: Participant Role was not populating on Schedule Reminder Form