pktgen: correct uninitialized queue_map

This fix a bug reported by backyes.
Right the first time pktgen's using queue_map that's not been initialized
by set_cur_queue_map(pkt_dev);
Signed-off-by: Junchang Wang <junchangwang@gmail.com>
Signed-off-by: Backyes <backyes@mail.ustc.edu.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/core/pktgen.c

@@ -2612,8 +2612,8 @@ static struct sk_buff *fill_packet_ipv4(struct net_device *odev,
 	/* Update any of the values, used when we're incrementing various
 	 * fields.
 	 */
-	queue_map = pkt_dev->cur_queue_map;
 	mod_cur_headers(pkt_dev);
+	queue_map = pkt_dev->cur_queue_map;
 
 	datalen = (odev->hard_header_len + 16) & ~0xf;
 
@@ -2976,8 +2976,8 @@ static struct sk_buff *fill_packet_ipv6(struct net_device *odev,
 	/* Update any of the values, used when we're incrementing various
 	 * fields.
 	 */
-	queue_map = pkt_dev->cur_queue_map;
 	mod_cur_headers(pkt_dev);
+	queue_map = pkt_dev->cur_queue_map;
 
 	skb = __netdev_alloc_skb(odev,
 				 pkt_dev->cur_pkt_size + 64