of: eliminate of_device->node and dev_archdata->{of,prom}_node

This patch eliminates the node pointer from struct of_device and the
of_node (or prom_node) pointer from struct dev_archdata since the node
pointer is now part of struct device proper when CONFIG_OF is set, and
all users of the old pointer locations have already been converted over
to use device->of_node.

Also remove dev_archdata_{get,set}_node() as it is no longer used by
anything.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

drivers/of/of_spi.c

@@ -80,7 +80,6 @@ void of_register_spi_devices(struct spi_master *master, struct device_node *np)
 		/* Store a pointer to the node in the device structure */
 		of_node_get(nc);
 		spi->dev.of_node = nc;
-		spi->dev.archdata.of_node = nc;
 
 		/* Register the new device */
 		request_module(spi->modalias);