net: reintroduce missing rcu_assign_pointer() calls

commit a9b3cd7f32 (rcu: convert uses of rcu_assign_pointer(x, NULL) to
RCU_INIT_POINTER) did a lot of incorrect changes, since it did a
complete conversion of rcu_assign_pointer(x, y) to RCU_INIT_POINTER(x,
y).

We miss needed barriers, even on x86, when y is not NULL.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Stephen Hemminger <shemminger@vyatta.com>
CC: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/decnet/dn_dev.c b/net/decnet/dn_dev.c
index 2ab16e1..74d321a 100644
--- a/net/decnet/dn_dev.c
+++ b/net/decnet/dn_dev.c
@@ -388,7 +388,7 @@
 	}
 
 	ifa->ifa_next = dn_db->ifa_list;
-	RCU_INIT_POINTER(dn_db->ifa_list, ifa);
+	rcu_assign_pointer(dn_db->ifa_list, ifa);
 
 	dn_ifaddr_notify(RTM_NEWADDR, ifa);
 	blocking_notifier_call_chain(&dnaddr_chain, NETDEV_UP, ifa);
@@ -1093,7 +1093,7 @@
 
 	memcpy(&dn_db->parms, p, sizeof(struct dn_dev_parms));
 
-	RCU_INIT_POINTER(dev->dn_ptr, dn_db);
+	rcu_assign_pointer(dev->dn_ptr, dn_db);
 	dn_db->dev = dev;
 	init_timer(&dn_db->timer);