Membership auto-renew options are not shown when multiple payment processors which support auto-renew are enabled for a contribution page

lines 746 + in CRM_Member_BAO_Membership::buildMembershipBlock aren't handing multiple processors properly. $allowAutoRenewOpt gets set to 0 if there are > 1 processors enabled (e.g. PayPal + Authnet)

if (is_array($paymentProcessor) &&
!CRM_Utils_Array::value(CRM_Utils_Array::value('payment_processor', $form->_values),$paymentProcessor))

{ $allowAutoRenewOpt = 0; }