nft: consolidate nft_rule_find for ARP, IPv4 and IPv6

This patch kills nft_arp_rule_find, which is almost a copy and paste
of the original nft_rule_find function. Refactor this function to
move specific protocol parts to the corresponding nft-{ipv4,ipv6,arp}.c
files.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
6 files changed