net_sched: make room for (struct qdisc_skb_cb)->pkt_segs

net_sched: make room for (struct qdisc_skb_cb)->pkt_segs

Add a new u16 field, next to pkt_len : pkt_segs

This will cache shinfo->gso_segs to speed up qdisc deqeue().

Move slave_dev_queue_mapping at the end of qdisc_skb_cb,
and move three bits from tc_skb_cb :
- post_ct
- post_ct_snat
- post_ct_dnat

Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20251121083256.674562-2-edumazet@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>