net: marvell: Use min() instead of doing it manually

Fix following coccicheck warning:
drivers/net/ethernet/marvell/mv643xx_eth.c:1664:35-36: WARNING opportunity for min()
Signed-off-by: Haowen Bai <baihaowen88@gmail.com>
Link: https://lore.kernel.org/r/1646271529-7659-1-git-send-email-baihaowen88@gmail.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/marvell/mv643xx_eth.c

@@ -1661,7 +1661,7 @@ mv643xx_eth_set_ringparam(struct net_device *dev, struct ethtool_ringparam *er,
 	if (er->rx_mini_pending || er->rx_jumbo_pending)
 		return -EINVAL;
 
-	mp->rx_ring_size = er->rx_pending < 4096 ? er->rx_pending : 4096;
+	mp->rx_ring_size = min(er->rx_pending, 4096U);
 	mp->tx_ring_size = clamp_t(unsigned int, er->tx_pending,
 				   MV643XX_MAX_SKB_DESCS * 2, 4096);
 	if (mp->tx_ring_size != er->tx_pending)