staging: brcm80211: fix checkpatch warning in fullmac

Fix the __aligned checkpatch warning in wl_cfg80211.h

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