be2net: Remove unnecessary frag list traversing.

This driver does not indicate support for frag lists.

Furthermore, even if it did, the code is walking the frag
lists incorrectly.  The idiom is:

	for (iter = skb_shinfo(skb)->frag_list; iter; iter = iter->next)

but it's doing:

	for (iter = skb_shinfo(skb)->frag_list; iter;
	     iter = skb_shinfo(iter)->frag_list)

which would never work.  And this proves that this driver never
saw an SKB with active frag lists.

So just remove the code altogether and the driver TX path becomes
much simpler.

Signed-off-by: David S. Miller <davem@davemloft.net>