netfilter: Add the missed return value check of nft_register_chain_type

There are some codes of netfilter module which did not check the return
value of nft_register_chain_type. Add the checks now.

Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
diff --git a/net/netfilter/nf_tables_inet.c b/net/netfilter/nf_tables_inet.c
index 6b5f762..f713cc2 100644
--- a/net/netfilter/nf_tables_inet.c
+++ b/net/netfilter/nf_tables_inet.c
@@ -82,7 +82,10 @@
 {
 	int ret;
 
-	nft_register_chain_type(&filter_inet);
+	ret = nft_register_chain_type(&filter_inet);
+	if (ret < 0)
+		return ret;
+
 	ret = register_pernet_subsys(&nf_tables_inet_net_ops);
 	if (ret < 0)
 		nft_unregister_chain_type(&filter_inet);