net: remove unused struct inet_frag_queue.fragments field

Now that all users of struct inet_frag_queue have been converted
to use 'rb_fragments', remove the unused 'fragments' field.

Build with `make allyesconfig` succeeded. ip_defrag selftest passed.

Signed-off-by: Peter Oskolkov <posk@google.com>
Acked-by: Stefan Schmidt <stefan@datenfreihafen.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ieee802154/6lowpan/reassembly.c

@@ -179,7 +179,6 @@ static int lowpan_frag_reasm(struct lowpan_frag_queue *fq, struct sk_buff *skb,
 
 	skb->dev = ldev;
 	skb->tstamp = fq->q.stamp;
-	fq->q.fragments = NULL;
 	fq->q.rb_fragments = RB_ROOT;
 	fq->q.fragments_tail = NULL;
 	fq->q.last_run_head = NULL;