netfilter: nft_redir: Make nft_redir_dump static

Fix sparse warning:

net/netfilter/nft_redir.c:85:5:
 warning: symbol 'nft_redir_dump' was not declared. Should it be static?
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

net/netfilter/nft_redir.c

@@ -82,7 +82,7 @@ static int nft_redir_init(const struct nft_ctx *ctx,
 	return nf_ct_netns_get(ctx->net, ctx->family);
 }
 
-int nft_redir_dump(struct sk_buff *skb, const struct nft_expr *expr)
+static int nft_redir_dump(struct sk_buff *skb, const struct nft_expr *expr)
 {
 	const struct nft_redir *priv = nft_expr_priv(expr);