netfilter: nft_ct: expectation timeouts are passed in milliseconds

netfilter: nft_ct: expectation timeouts are passed in milliseconds

Userspace passes '5000' in case user asks for 5 seconds.

Allowing for sub-second expectation lifetimes makes sense to me. so
fix up the kernel side instead of munging nft to send a value rounded
up to next second.

Also note that this violates nft convention of passing integers in
network byte order, but we can't change this anymore.

Fixes: 857b46027d6f ("netfilter: nft_ct: add ct expectations support")
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>