libata: fix ata_eh_suspend() return value

ata_eh_suspend() was returning 0 regardless of failure.  This bug has
potential to lose data on suspend.  Fix it.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

drivers/ata/libata-eh.c

@@ -1796,7 +1796,7 @@ static int ata_eh_suspend(struct ata_port *ap, struct ata_device **r_failed_dev)
 		*r_failed_dev = dev;
 
 	DPRINTK("EXIT\n");
-	return 0;
+	return rc;
 }
 
 /**