net: dev: rename queue selection helpers.

With the following patches, we are going to use __netdev_pick_tx() in
many modules. Rename it to netdev_pick_tx(), to make it clear is
a public API.

Also rename the existing netdev_pick_tx() to netdev_core_pick_tx(),
to avoid name clashes.

Suggested-by: Eric Dumazet <edumazet@google.com>
Suggested-by: David Miller <davem@davemloft.net>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/xfrm/xfrm_device.c b/net/xfrm/xfrm_device.c
index b8736f5..2db1626 100644
--- a/net/xfrm/xfrm_device.c
+++ b/net/xfrm/xfrm_device.c
@@ -247,7 +247,7 @@ void xfrm_dev_resume(struct sk_buff *skb)
 	unsigned long flags;
 
 	rcu_read_lock();
-	txq = netdev_pick_tx(dev, skb, NULL);
+	txq = netdev_core_pick_tx(dev, skb, NULL);
 
 	HARD_TX_LOCK(dev, txq, smp_processor_id());
 	if (!netif_xmit_frozen_or_stopped(txq))