ata_qc_complete — Complete an active ATA command
|struct ata_queued_cmd * qc|
Indicate to the mid and upper layers that an ATA command has completed, with either an ok or not-ok status.
Refrain from calling this function multiple times when
successfully completing multiple NCQ commands.
ata_qc_complete_multiple should be used instead, which will
properly update IRQ expect state.
LOCKING: spin_lock_irqsave(host lock)