Staging: brcm80211: remove driver specific -W options

A single driver shouldn't be overriding the kernel-wide -W options.
This removes them from the Makefile.

Bonus is that the code at least now will build on a 64bit platform.
Problem is that both drivers can't be built at the same time right now
or bad things happen when linking.

Cc: Henry Ptasinski <henryp@broadcom.com>
Cc: Nohee Ko <noheek@broadcom.com>
Cc: jason <jason@lakedaemon.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>