rt2x00: Wakeup hardware before loading firmware

According to the legacy drivers the AUTOWAKEUP_CFG
register must be reset to 0 before loading the firmware.

Instead of during rt2800{pci,usb}_write_firmware it
must actually be done in rt2800_load_firmware() before
resetting the WPDMA_GLO_CFG and PWR_PIN_CFG registers.

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