[SCSI] libsas: don't mark expanders as gone when a child device is removed

Commit 56dd2c06 "[SCSI] libsas: Don't issue commands to devices that
have been hot-removed" marked the parent device of an end-device as gone
when all the phys to the end device have been deleted.

The expander device is still present until its parent is removed.  This
is a benign change until the smp_execute_task() path is taught to check
->gone.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

drivers/scsi/libsas/sas_expander.c

@@ -1820,7 +1820,6 @@ static void sas_unregister_devs_sas_addr(struct domain_device *parent,
 				break;
 			}
 		}
-		set_bit(SAS_DEV_GONE, &parent->state);
 		sas_disable_routing(parent, phy->attached_sas_addr);
 	}
 	memset(phy->attached_sas_addr, 0, SAS_ADDR_SIZE);