scsi: libsas: remove irq save in sas_ata_qc_issue()

Since commit 312d3e56 ("[SCSI] libsas: remove ata_port.lock management
duties from lldds") the sas_ata_qc_issue() function unlocks the
ata_port.lock and disables interrupts before doing so.  That lock is always
taken with disabled interrupts so at this point, the interrupts are already
disabled. There is no need to disable the interrupts before the unlock
operation because they are already disabled.  Restoring the interrupt state
later does not change anything because they were disabled and remain
disabled. Therefore remove the operations which do not change the
behaviour.

Fixes: 312d3e56 ("[SCSI] libsas: remove ata_port.lock management duties from lldds")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>