RFKILL: fix input layer initialisation

Initialise correctly last fields, so tasks can be actually executed.
On some architectures the initial jiffies value is not zero, so later
all rfkill incorrectly decides that rfkill_*.last is in future.

Signed-off-by: Dmitry Baryshkov <dbaryshkov@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>