spidernet: node-aware skbuff allocation

Spidernet was the driver I original did all the node-aware netdevice
allocation for, but after a year it still hasn't hit mainline.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>