drivers:net: Remove unnecessary OOM messages after netdev_alloc_skb

Emitting netdev_alloc_skb and netdev_alloc_skb_ip_align OOM
messages is unnecessary as there is already a dump_stack
after allocation failures.

Other trivial changes around these removals:

Convert a few comparisons of pointer to 0 to !pointer.
Change flow to remove unnecessary label.
Remove now unused variable.
Hoist assignment from if.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
index 278c9db..397d4a6 100644
--- a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
+++ b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c
@@ -235,10 +235,8 @@
 				      ((i + 1) % RX_BD_NUM);
 
 		skb = netdev_alloc_skb_ip_align(ndev, lp->max_frm_size);
-		if (!skb) {
-			dev_err(&ndev->dev, "alloc_skb error %d\n", i);
+		if (!skb)
 			goto out;
-		}
 
 		lp->rx_bd_v[i].sw_id_offset = (u32) skb;
 		lp->rx_bd_v[i].phys = dma_map_single(ndev->dev.parent,
@@ -777,10 +775,9 @@
 		packets++;
 
 		new_skb = netdev_alloc_skb_ip_align(ndev, lp->max_frm_size);
-		if (!new_skb) {
-			dev_err(&ndev->dev, "no memory for new sk_buff\n");
+		if (!new_skb)
 			return;
-		}
+
 		cur_p->phys = dma_map_single(ndev->dev.parent, new_skb->data,
 					     lp->max_frm_size,
 					     DMA_FROM_DEVICE);