Replace kfree_skb with dev_kfree_skb_any in vlan_insert_tag as
vlan_insert_tag can be called from hard irq context (netpoll)
and from other contexts.

dev_kfree_skb_any is used as vlan_insert_tag only frees the skb if the
skb can not be modified to insert a tag, in which case vlan_insert_tag
drops the skb.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>