netfilter: xtables: move ipt_ecn to xt_ecn

Prepare the ECN match for augmentation by an IPv6 counterpart. Since
no symbol dependencies to ipv6.ko are added, having a single ecn match
module is the more so welcome.

Signed-off-by: Jan Engelhardt <[email protected]>
Signed-off-by: Pablo Neira Ayuso <[email protected]>
8 files changed