This is not only for readability but also for optimization.
What we do here is to build the 32bit word at the beginning of the ipv6
header (the "ip6_flow" virtual member of struct ip6_hdr in RFC3542) and
we do not need to read the tclass portion of the target buffer.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>