net: rbridge: fix vni_del_port

fix vni_del_port in order to remove empty vni

Signed-off-by: Ahmed Amamou <ahmed@gandi.net>
net: bridge: fix memleak when destroying skb

due to a typo some kfree(skb) have replaced the expected kfree_skb(skb)
such incorrect free will result in a memleak

Signed-off-by: Ahmed Amamou <ahmed@gandi.net>
Signed-off-by: William Dauchy <william@gandi.net>