Use DECLARE_FLEX_ARRAY() helper in include/net/netns/generic.h

[GustavoARSilva]

diff -u -p ./include/net/netns/generic.h /tmp/nothing/include/net/netns/generic.h
--- ./include/net/netns/generic.h
+++ /tmp/nothing/include/net/netns/generic.h
@@ -33,7 +33,6 @@ struct net_generic {
                        struct rcu_head rcu;
                } s;

-               void *ptr[0];
        };
 };