skbuff: skb_segment: s/skb/head_skb/
skbuff: skb_segment: s/skb/head_skb/

rename local variable to make it easier to tell at a glance that we are
dealing with a head skb.

Signed-off-by: Michael S. Tsirkin <255103e50249e3d658441816e0597170ebfc16ef@redhat.com>
Signed-off-by: David S. Miller <fe08d3c717adf2ae63592e4c9aec6e3e404d8e3e@davemloft.net>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs