net: ipv6: remove 'next' member from inet6_dev

The next pointer within the inet6_dev structure seems not to be used
anywhere. So just remove it. Tested with allmodconfig on x86_64.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/if_inet6.h b/include/net/if_inet6.h
index 0727d0e..e07feb4 100644
--- a/include/net/if_inet6.h
+++ b/include/net/if_inet6.h
@@ -193,7 +193,6 @@
 	struct in6_addr		token;
 
 	struct neigh_parms	*nd_parms;
-	struct inet6_dev	*next;
 	struct ipv6_devconf	cnf;
 	struct ipv6_devstat	stats;
 	unsigned long		tstamp; /* ipv6InterfaceTable update timestamp */