net: faraday: ftmac100: Use BUG_ON instead of if condition followed by BUG.

Notice that in this particular case unlikely() is already being called
inside BUG_ON macro.

This issue was detected with the help of Coccinelle.
Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/faraday/ftmac100.c

@@ -402,6 +402,7 @@ static bool ftmac100_rx_packet(struct ftmac100 *priv, int *processed)
 	struct page *page;
 	dma_addr_t map;
 	int length;
+	bool ret;
 
 	rxdes = ftmac100_rx_locate_first_segment(priv);
 	if (!rxdes)
@@ -416,8 +417,8 @@ static bool ftmac100_rx_packet(struct ftmac100 *priv, int *processed)
 	 * It is impossible to get multi-segment packets
 	 * because we always provide big enough receive buffers.
 	 */
-	if (unlikely(!ftmac100_rxdes_last_segment(rxdes)))
-		BUG();
+	ret = ftmac100_rxdes_last_segment(rxdes);
+	BUG_ON(!ret);
 
 	/* start processing */
 	skb = netdev_alloc_skb_ip_align(netdev, 128);