fec: remove unnecessary cast

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/fec.c b/drivers/net/fec.c
index f8396fb..e03b177 100644
--- a/drivers/net/fec.c
+++ b/drivers/net/fec.c
@@ -1660,11 +1660,10 @@
 	struct bufdesc *bdp, *cbd_base;
 	int 		i, j;
 
-	/* Allocate memory for buffer descriptors.
-	*/
-	mem_addr = (unsigned long)dma_alloc_coherent(NULL, PAGE_SIZE,
-			&fep->bd_dma, GFP_KERNEL);
-	if (mem_addr == 0) {
+	/* Allocate memory for buffer descriptors. */
+	cbd_base = dma_alloc_coherent(NULL, PAGE_SIZE, &fep->bd_dma,
+			GFP_KERNEL);
+	if (!cbd_base) {
 		printk("FEC: allocate descriptor memory failed?\n");
 		return -ENOMEM;
 	}
@@ -1698,10 +1697,7 @@
 	}
 #endif
 
-	cbd_base = (struct bufdesc *)mem_addr;
-
-	/* Set receive and transmit descriptor base.
-	*/
+	/* Set receive and transmit descriptor base. */
 	fep->rx_bd_base = cbd_base;
 	fep->tx_bd_base = cbd_base + RX_RING_SIZE;