Staging: wlan-ng: Move firmware loading into driver

Move prism2 firmware loading from userspace into driver, using linux
request_firmware(). Firmware is now loaded (if available) on device
probing, before it is registered as a netdevice and advertised to userspace.

Signed-off-by: Karl Relton <karllinuxtest.relton@ntlworld.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>