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>