netfilter: nfnetlink: pass down netns pointer to call() and call_rcu()

Adapt callsites to avoid recurrent lookup of the netns pointer.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
diff --git a/net/netfilter/nft_compat.c b/net/netfilter/nft_compat.c
index 9c8fab0..454841b 100644
--- a/net/netfilter/nft_compat.c
+++ b/net/netfilter/nft_compat.c
@@ -519,9 +519,9 @@
 	return -1;
 }
 
-static int
-nfnl_compat_get(struct sock *nfnl, struct sk_buff *skb,
-		const struct nlmsghdr *nlh, const struct nlattr * const tb[])
+static int nfnl_compat_get(struct net *net, struct sock *nfnl,
+			   struct sk_buff *skb, const struct nlmsghdr *nlh,
+			   const struct nlattr * const tb[])
 {
 	int ret = 0, target;
 	struct nfgenmsg *nfmsg;