vlan: Calling vlan_hwaccel_do_receive() is always valid.

It is now acceptable to receive vlan tagged packets at any time,
even if CONFIG_VLAN_8021Q is not set.  This means that calling
vlan_hwaccel_do_receive() should not result in BUG() but rather just
behave as if there were no vlan devices configured.
Reported-by: NVladislav Zolotarov <vladz@broadcom.com>
Signed-off-by: NJesse Gross <jesse@nicira.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include/linux/if_vlan.h

@@ -168,7 +168,8 @@ static inline int __vlan_hwaccel_rx(struct sk_buff *skb, struct vlan_group *grp,
 
 static inline bool vlan_hwaccel_do_receive(struct sk_buff **skb)
 {
-	BUG();
+	if ((*skb)->vlan_tci & VLAN_VID_MASK)
+		(*skb)->pkt_type = PACKET_OTHERHOST;
 	return false;
 }