--- zzzz-none-000/linux-4.1.52/include/net/transp_v6.h	2018-05-28 02:26:45.000000000 +0000
+++ bcm63-7530ax-731/linux-4.1.52/include/net/transp_v6.h	2022-03-02 11:37:13.000000000 +0000
@@ -51,6 +51,10 @@
 
 /* address family specific functions */
 extern const struct inet_connection_sock_af_ops ipv4_specific;
+#if defined(CONFIG_BCM_MPTCP) && defined(CONFIG_BCM_KF_MPTCP)
+extern const struct inet_connection_sock_af_ops ipv6_mapped;
+extern const struct inet_connection_sock_af_ops ipv6_specific;
+#endif
 
 void inet6_destroy_sock(struct sock *sk);