Staging: wlan-ng: Purge all MIBs not used internally.

The next step is to bypass the MIB calling mechanism altogether and just
invoke the hardware directly where needed, but at least now the list has
been paired down considerably.

Signed-off-by: Solomon Peachy <pizza@shaftnet.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>