htb: remove two unnecessary assignments

remove two unnecessary assignments

we don't need to assign NULL when initialize structure objects.

Signed-off-by: Changli Gao <xiaosuo@gmail.com>
----
 net/sched/sch_htb.c |    2 --
 1 file changed, 2 deletions(-)
Signed-off-by: David S. Miller <davem@davemloft.net>