Fix DCR getwork jobmaker ordering
Fix DCR getwork jobmaker ordering

There is a typo in DCR jobmaker. The getwork object needs to be ordered
by creation time but not data.

btccom/btcpool,btccom/btcpool,btccom/btcpool,btccom/btcpool,btccom/btcpool,btccom/btcpool,btccom/btcpool,btccom/btcpool