To prepare for future IPv6 NAT functions. - Rename common ipv4_nat_xxx to nat_xxx - Move some common definitions into header Signed-off-by: Zhe Weng <wengzhe@xiaomi.com>
To prepare for future IPv6 NAT functions. - Rename common ipv4_nat_xxx to nat_xxx - Move some common definitions into header Signed-off-by: Zhe Weng <wengzhe@xiaomi.com>