[NETFILTER]: xt_connmark match, revision 1

Introduces the xt_connmark match revision 1. It uses fixed types,
eventually obsoleting revision 0 some day (uses nonfixed types).
(Unfixed types like "unsigned long" do not play well with mixed
user-/kernelspace "bitness", e.g. 32/64, as is common on SPARC64,
and need extra compat code.)

Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>