drivers:net: Convert dma_alloc_coherent(...__GFP_ZERO) to dma_zalloc_coherent

__GFP_ZERO is an uncommon flag and perhaps is better
not used.  static inline dma_zalloc_coherent exists
so convert the uses of dma_alloc_coherent with __GFP_ZERO
to the more common kernel style with zalloc.

Remove memset from the static inline dma_zalloc_coherent
and add just one use of __GFP_ZERO instead.

Trivially reduces the size of the existing uses of
dma_zalloc_coherent.

Realign arguments as appropriate.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/sgi/meth.c b/drivers/net/ethernet/sgi/meth.c
index 9f5f35e..770036b 100644
--- a/drivers/net/ethernet/sgi/meth.c
+++ b/drivers/net/ethernet/sgi/meth.c
@@ -212,9 +212,8 @@
 static int meth_init_tx_ring(struct meth_private *priv)
 {
 	/* Init TX ring */
-	priv->tx_ring = dma_alloc_coherent(NULL, TX_RING_BUFFER_SIZE,
-	                                   &priv->tx_ring_dma,
-					   GFP_ATOMIC | __GFP_ZERO);
+	priv->tx_ring = dma_zalloc_coherent(NULL, TX_RING_BUFFER_SIZE,
+					    &priv->tx_ring_dma, GFP_ATOMIC);
 	if (!priv->tx_ring)
 		return -ENOMEM;