libata-scsi: fix MODE SELECT translation for Control mode page

scsi_done() was called repeatedly and apparently because of that,
the kernel would call trace when we touch the Control mode page:

Call Trace:
[<ffffffff812ea0d2>] dump_stack+0x63/0x81
[<ffffffff81079cfb>] __warn+0xcb/0xf0
[<ffffffff81079e2d>] warn_slowpath_null+0x1d/0x20
[<ffffffffa00f51b0>] ata_eh_finish+0xe0/0xf0 [libata]
[<ffffffffa00fb830>] sata_pmp_error_handler+0x640/0xa50 [libata]
[<ffffffffa00470ed>] ahci_error_handler+0x1d/0x70 [libahci]
[<ffffffffa00f55f0>] ata_scsi_port_error_handler+0x430/0x770 [libata]
[<ffffffffa00eff8d>] ? ata_scsi_cmd_error_handler+0xdd/0x160 [libata]
[<ffffffffa00f59d7>] ata_scsi_error+0xa7/0xf0 [libata]
[<ffffffffa00913ba>] scsi_error_handler+0xaa/0x560 [scsi_mod]
[<ffffffffa0091310>] ? scsi_eh_get_sense+0x180/0x180 [scsi_mod]
[<ffffffff81098eb8>] kthread+0xd8/0xf0
[<ffffffff815d913f>] ret_from_fork+0x1f/0x40
[<ffffffff81098de0>] ? kthread_worker_fn+0x170/0x170
---[ end trace 8b7501047e928a17 ]---

Removed the unnecessary code and let ata_scsi_translate() do the job.

Also, since ata_mselect_control() has no ATA command to send to the
device, ata_scsi_mode_select_xlat() should return 1 for it, so that
ata_scsi_translate() will finish early to avoid ata_qc_issue().

Signed-off-by: Tom Yan <[e-mail]>
Signed-off-by: Tejun Heo <[e-mail]>

drivers/ata/libata-scsi.c

···
 		dev->flags |= ATA_DFLAG_D_SENSE;
 	else
 		dev->flags &= ~ATA_DFLAG_D_SENSE;
-	qc->scsicmd->result = SAM_STAT_GOOD;
-	qc->scsicmd->scsi_done(qc->scsicmd);
 	return 0;
 }
 
···
 		if (ata_mselect_control(qc, p, pg_len, &fp) < 0) {
 			fp += hdr_len + bd_len;
 			goto invalid_param;
+		} else {
+			goto skip; /* No ATA command to send */
 		}
 		break;
 	default:		/* invalid page code */