ravb: Add stats_len to struct ravb_hw_info

R-Car provides 30 device stats, whereas RZ/G2L provides only 15. In
addition, RZ/G2L has stats "rx_queue_0_csum_offload_errors" instead of
"rx_queue_0_missed_errors".

Replace RAVB_STATS_LEN macro with a structure variable stats_len to
struct ravb_hw_info, to support subsequent SoCs without any code changes
to the ravb_get_sset_count function.
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Sergei Shtylyov <sergei.shtylyov@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/renesas/ravb.h

@@ -990,6 +990,7 @@ enum ravb_chip_id {
 
 struct ravb_hw_info {
 	enum ravb_chip_id chip_id;
+	int stats_len;
 	size_t max_rx_len;
 	unsigned aligned_tx: 1;
 };

drivers/net/ethernet/renesas/ravb_main.c

@@ -1133,13 +1133,14 @@ static const char ravb_gstrings_stats[][ETH_GSTRING_LEN] = {
 	"rx_queue_1_over_errors",
 };
 
-#define RAVB_STATS_LEN	ARRAY_SIZE(ravb_gstrings_stats)
-
 static int ravb_get_sset_count(struct net_device *netdev, int sset)
 {
+	struct ravb_private *priv = netdev_priv(netdev);
+	const struct ravb_hw_info *info = priv->info;
+
 	switch (sset) {
 	case ETH_SS_STATS:
-		return RAVB_STATS_LEN;
+		return info->stats_len;
 	default:
 		return -EOPNOTSUPP;
 	}
@@ -1926,11 +1927,13 @@ static int ravb_mdio_release(struct ravb_private *priv)
 
 static const struct ravb_hw_info ravb_gen3_hw_info = {
 	.chip_id = RCAR_GEN3,
+	.stats_len = ARRAY_SIZE(ravb_gstrings_stats),
 	.max_rx_len = RX_BUF_SZ + RAVB_ALIGN - 1,
 };
 
 static const struct ravb_hw_info ravb_gen2_hw_info = {
 	.chip_id = RCAR_GEN2,
+	.stats_len = ARRAY_SIZE(ravb_gstrings_stats),
 	.max_rx_len = RX_BUF_SZ + RAVB_ALIGN - 1,
 	.aligned_tx = 1,
 };