staging: brcm80211: remove unused module from softmac driver

The softmac driver contained an event queue mechanism which
was properly initialized and queried but no event are ever
posted to it. Therefor the module has been removed.

Reviewed-by: Roland Vossen <rvossen@broadcom.com>
Reviewed-by: Brett Rudley <brudley@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>