resync rfkill.h with kernel

resync rfkill.h with kernel

The kernel rfkill.h got a new license thanks to all
people involved with it -- we can now sync with it
and clean up the little license mess here. The
upstream (kernel) commit was:

commit 8bc11b491b6cad75e737f1d38bb4b261bd95b291
Author: Johannes Berg <johannes@sipsolutions.net>
Date:   Wed Aug 26 18:13:17 2009 +0200

    rfkill: relicense header file

    This header file is copied into userspace tools that
    need not be GPLv2 licensed, make that easier.

    Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
    Acked-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
    Acked-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
    Acked-by: Iñaky Pérez-González <inaky@linux.intel.com>
    Acked-by: Ivo van Doorn <IvDoorn@gmail.com>
    Acked-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
    Acked-by: Michael Buesch <mb@bu3sch.de>
    Acked-by: Tomas Winkler <tomas.winkler@intel.com>
    Signed-off-by: John W. Linville <linville@tuxdriver.com>