net: emaclite: Use calloc instead of malloc

Simplify driver logic and clear eth_device structure
in one command.

Signed-off-by: Michal Simek <monstr@monstr.eu>
diff --git a/drivers/net/xilinx_emaclite.c b/drivers/net/xilinx_emaclite.c
index 2a5c5e1..28aab97 100644
--- a/drivers/net/xilinx_emaclite.c
+++ b/drivers/net/xilinx_emaclite.c
@@ -344,11 +344,10 @@
 {
 	struct eth_device *dev;
 
-	dev = malloc(sizeof(*dev));
+	dev = calloc(1, sizeof(*dev));
 	if (dev == NULL)
 		return -1;
 
-	memset(dev, 0, sizeof(*dev));
 	sprintf(dev->name, "Xelite.%x", base_addr);
 
 	dev->iobase = base_addr;