caif: Fix function NULL pointer check.

Check that receive function pointer is not null before calling it.

Signed-off-by: Sjur Braendeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/caif/caif_dev.c b/net/caif/caif_dev.c
index 0fd01dd..b99369a 100644
--- a/net/caif/caif_dev.c
+++ b/net/caif/caif_dev.c
@@ -173,7 +173,7 @@
 	net = dev_net(dev);
 	pkt = cfpkt_fromnative(CAIF_DIR_IN, skb);
 	caifd = caif_get(dev);
-	if (!caifd || !caifd->layer.up || !caifd->layer.up->ctrlcmd)
+	if (!caifd || !caifd->layer.up || !caifd->layer.up->receive)
 		return NET_RX_DROP;
 
 	if (caifd->layer.up->receive(caifd->layer.up, pkt))