Bug:#1381176 1) When vlan tagged packet is received, skb is marked as tagged, wihtout a tag in the packet.  In Vrouter, tag is inserted in vr_packet without modifying skb length or data. This leads to a problem after vr_preset(). In vmware, when vlan tagged packetd is received, if it needs to be trapped to agent, packet is getting corrupted on pkt0 as vr_preset() does not consider the extra 4 bytes of vlan tag. As a fix, vlan tag is inserted in skb itself.  2) When Host OS sends some packets to VM on Esxi, packets to Esxi VM will be tagge by Vrouter in encap nexthop. But in reserver path, packets from VM will have a vlan tag which need to be removed before giving to Vhost. This is added as an explicit check from Virtual vlan interface to Vhost to ensure no other recv_nh packets are effected.

Change-Id: Idfeaed60e42d07d8a74ce69fd53565188eab4a80