staging: brcm80211: get rid of PKT[TO/FROM]NATIVE macros

These macros are not needed in a linux-only driver and have been
removed.

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