scsi: hisi_sas: Fix spin lock management in slot_index_alloc_quirk_v2_hw()

scsi: hisi_sas: Fix spin lock management in slot_index_alloc_quirk_v2_hw()

BugLink: https://bugs.launchpad.net/bugs/1810457
Currently a spin_unlock_irqrestore() call is missing on the error path,
so add it.

Reported-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
(cherry picked from commit fe5fb42de36227c1c2dbb1e7403329ec8a915c20)
Signed-off-by: dann frazier <dann.frazier@canonical.com>
Acked-by: Stefan Bader <stefan.bader@canonical.com>
Acked-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>