Include the allocated portion of reserved resources in the role sorter for DRF.

Reserved resources should be accounted for fairness calculation whether they are allocated or not, since they model a long or forever running task. That is, the effect of reserving resources is equivalent to launching a task in that the resources that make up the reservation are not available to other roles as non-revocable.

In the short-term, we should at least account for the allocated portion of the reservation.