rt2x00: Use struct rt2x00_dev driver data in rt2800{pci,usb}.

Start using the struct rt2x00_dev driver data in rt2800 for the calibration
data.

Signed-off-by: Gertjan van Wingerde <gwingerde@gmail.com>
Acked-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>