staging: brcm80211: remove some bsscfg attribute that are redundant

In the struct wlc_bsscfg a couple of attribute were held under a
preprocessor definition, but these are not needed in the mac80211
driver context.

Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>