staging: brcm80211: remove warning introduced by rfkill implementation

During rfkill implementation the content of wlc_radio_upd function
was removed for testing purposes only. This ended up in the patch
sent out. This commit restores the function content, which was the
only function calling static function wlc_radio_enable. This removes
the compilation warning observed.

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