arcnet: Remove pointer comparisons to NULL

Use direct tests of pointer instead.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
diff --git a/drivers/net/arcnet/capmode.c b/drivers/net/arcnet/capmode.c
index de80d9e..a898647 100644
--- a/drivers/net/arcnet/capmode.c
+++ b/drivers/net/arcnet/capmode.c
@@ -56,7 +56,7 @@
 		ofs = 256 - length;
 
 	skb = alloc_skb(length + ARC_HDR_SIZE + sizeof(int), GFP_ATOMIC);
-	if (skb == NULL) {
+	if (!skb) {
 		dev->stats.rx_dropped++;
 		return;
 	}
@@ -196,7 +196,7 @@
 
 	/* Now alloc a skb to send back up through the layers: */
 	ackskb = alloc_skb(length + ARC_HDR_SIZE, GFP_ATOMIC);
-	if (ackskb == NULL)
+	if (!ackskb)
 		goto free_outskb;
 
 	skb_put(ackskb, length + ARC_HDR_SIZE);