net: smc911x: Replace malloc()+memset() with calloc()

Replace combination of malloc()+memset() with calloc() as the behavior
is exactly the same and the amount of code is reduced.

Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Joe Hershberger <joe.hershberger@ni.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
diff --git a/drivers/net/smc911x.c b/drivers/net/smc911x.c
index 24b4eae..2c72e34 100644
--- a/drivers/net/smc911x.c
+++ b/drivers/net/smc911x.c
@@ -242,11 +242,9 @@
 	unsigned long addrl, addrh;
 	struct eth_device *dev;
 
-	dev = malloc(sizeof(*dev));
-	if (!dev) {
-		return -1;
-	}
-	memset(dev, 0, sizeof(*dev));
+	dev = calloc(1, sizeof(*dev));
+	if (!dev)
+		return -ENOMEM;
 
 	dev->iobase = base_addr;