libata: remove reading alt_status from ata_hsm_qc_complete()

In ata_hsm_qc_complete():
Calling ata_altstatus() after the qc is completed might race with next qc. Remove it.

Signed-off-by: Albert Lee <albertcc@tw.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>