[IPV6]: export inet6_sock_nr

Please apply, SCTP/DCCP needs this when INET_REFCNT_DEBUG
is set.
Signed-off-by: NArnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv6/af_inet6.c

@@ -88,6 +88,7 @@ int sysctl_ipv6_bindv6only;
 
 #ifdef INET_REFCNT_DEBUG
 atomic_t inet6_sock_nr;
+EXPORT_SYMBOL(inet6_sock_nr);
 #endif
 
 /* The inetsw table contains everything that inet_create needs to