The maximum descriptor size that can be specified on the reception side for
R-Car is 2048 bytes, whereas for RZ/G2L it is 8096.

Add the skb_size variable to struct ravb_hw_info for allocating different
skb buffer sizes for R-Car and RZ/G2L using the netdev_alloc_skb function.

Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
---
v2:
 * Incorporated Andrew and Sergei's review comments for making it smaller patch
   and provided detailed description.
---
 drivers/net/ethernet/renesas/ravb.h      |  1 +
 drivers/net/ethernet/renesas/ravb_main.c | 10 ++++++----
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/renesas/ravb.h b/drivers/net/ethernet/renesas/ravb.h
index cfb972c05b34..16d1711a0731 100644
--- a/drivers/net/ethernet/renesas/ravb.h
+++ b/drivers/net/ethernet/renesas/ravb.h

@@ -991,6 +991,7 @@ enum ravb_chip_id {
 struct ravb_hw_info {
 	enum ravb_chip_id chip_id;
 	int num_tx_desc;
+	size_t skb_sz;