brcm80211: add endian annotation to packet filter structures

The packet filter structures were byte copied and transferred over the
host bus to the device. As such they are little endian and have been
annotated accordingly.

Reported-by: Johannes Berg <johannes@sipsolutions.net>
Reviewed-by: Franky (Zhenhui) Lin <frankyl@broadcom.com>
Reviewed-by: Roland Vossen <rvossen@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>