clang with W=1 reports
drivers/net/ethernet/alteon/acenic.c:2438:10: error: variable
  'len' set but not used [-Werror,-Wunused-but-set-variable]
                int i, len = 0;
                       ^
This variable is not used so remove it.
Signed-off-by: Tom Rix <trix@redhat.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
        } else {
                dma_addr_t mapping;
                u32 vlan_tag = 0;
-               int i, len = 0;
+               int i;
 
                mapping = ace_map_tx_skb(ap, skb, NULL, idx);
                flagsize = (skb_headlen(skb) << 16);
                        const skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
                        struct tx_ring_info *info;
 
-                       len += skb_frag_size(frag);
                        info = ap->skb->tx_skbuff + idx;
                        desc = ap->tx_ring + idx;