libata: minor cleanups

A few code shuffles, to make merging future code easier.

Add (DRIVER_SENSE << 24) to certain result codes, as noted by Douglas
Gilbert.
diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index f731bbd..d568914 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -3131,14 +3131,14 @@
 	DPRINTK("ENTER\n");
 
 	qc = ata_qc_from_tag(ap, ap->active_tag);
-	if (!qc) {
+	if (qc)
+		ata_qc_timeout(qc);
+	else {
 		printk(KERN_ERR "ata%u: BUG: timeout without command\n",
 		       ap->id);
 		goto out;
 	}
 
-	ata_qc_timeout(qc);
-
 out:
 	DPRINTK("EXIT\n");
 }