net: remove netdev_alloc_page and use __GFP_COLD

Given we dont use anymore the struct net_device *dev argument, and this
interface brings litle benefit, remove netdev_{alloc|free}_page(), to
debloat include/linux/skbuff.h a bit.

(Some drivers used a mix of these interfaces and alloc_pages())

When allocating a page given to device for DMA transfer (device to
memory), it makes sense to use a cold one (__GFP_COLD)

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
CC: Dimitris Michailidis <dm@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
index 820fc04..1b28ed9 100644
--- a/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
+++ b/drivers/net/ethernet/intel/ixgbe/ixgbe_main.c
@@ -1140,7 +1140,7 @@
 
 		if (ring_is_ps_enabled(rx_ring)) {
 			if (!bi->page) {
-				bi->page = netdev_alloc_page(rx_ring->netdev);
+				bi->page = alloc_page(GFP_ATOMIC | __GFP_COLD);
 				if (!bi->page) {
 					rx_ring->rx_stats.alloc_rx_page_failed++;
 					goto no_buffers;