netfilter: nft_meta_bridge: Add NFT_META_BRI_IIFVPROTO support

This patch allows you to match on bridge vlan protocol, eg.

nft add rule bridge firewall zones counter meta ibrvproto 0x8100

Signed-off-by: wenxu <wenxu@ucloud.cn>
Reviewed-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>