[SCSI] libsas: remove ata_port.lock management duties from lldds

Each libsas driver (mvsas, pm8001, and isci) has invented a different
method for managing the ap->lock.  The lock is held by the ata
->queuecommand() path.  mvsas drops it prior to acquiring any internal
locks which allows it to hold its internal lock across calls to
task->task_done().  This capability is important as it is the only way
the driver can flush task->task_done() instances to guarantee that it no
longer has any in-flight references to a domain_device at
->lldd_dev_gone() time.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
diff --git a/drivers/scsi/isci/request.c b/drivers/scsi/isci/request.c
index 751368b..788daee 100644
--- a/drivers/scsi/isci/request.c
+++ b/drivers/scsi/isci/request.c
@@ -3796,8 +3796,7 @@
 		/* Cause this task to be scheduled in the SCSI error
 		 * handler thread.
 		 */
-		isci_execpath_callback(ihost, task,
-				       sas_task_abort);
+		sas_task_abort(task);
 
 		/* Change the status, since we are holding
 		 * the I/O until it is managed by the SCSI