rfkill: yet more minor kernel-doc fixes

For some stupid reason, I sent and old version of the patch minor kernel
doc-fix patch, and it got merged before I noticed the problem. This is an
incremental fix on top.

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Acked-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>