net: cleanup some rcu_dereference_raw

RCU api had been completed and rcu_access_pointer() or
rcu_dereference_protected() are better than generic
rcu_dereference_raw()

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index 0a4db02..4330db9 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -1578,7 +1578,7 @@
 		new = kzalloc(sizeof(*new) + NLGRPSZ(groups), GFP_ATOMIC);
 		if (!new)
 			return -ENOMEM;
-		old = rcu_dereference_raw(tbl->listeners);
+		old = rcu_dereference_protected(tbl->listeners, 1);
 		memcpy(new->masks, old->masks, NLGRPSZ(tbl->groups));
 		rcu_assign_pointer(tbl->listeners, new);