spi doesn't need class_device

Make the SPI framework and drivers stop using class_device.  Update docs
accordingly ...  highlighting just which sysfs paths should be
"safe"/stable.

Signed-off-by: Tony Jones <tonyj@suse.de>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Greg KH <greg@kroah.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/spi/pxa2xx_spi.c b/drivers/spi/pxa2xx_spi.c
index e05918e..5f3d808 100644
--- a/drivers/spi/pxa2xx_spi.c
+++ b/drivers/spi/pxa2xx_spi.c
@@ -1242,7 +1242,7 @@
 
 	INIT_WORK(&drv_data->pump_messages, pump_messages);
 	drv_data->workqueue = create_singlethread_workqueue(
-					drv_data->master->cdev.dev->bus_id);
+					drv_data->master->dev.parent->bus_id);
 	if (drv_data->workqueue == NULL)
 		return -EBUSY;